The teacher will be very surprised to see your correct solution 😉
_____________________________________________________________________ / ________________________________________ / / 2 3 / / / 3 \ / 2 \ / / |2*b 27*d 9*b*c| |b 3*c| / / |---- + ---- - -----| - 4*|-- - ---| / / | 3 a 2 | | 2 a | 3 2 / \/ \ a a / \a / b 27*d 9*b*c b 3*c / ----------------------------------------------- + -- + ---- - ----- -- - --- 3 / 2 3 2*a 2 2 a \/ a 2*a b a x_1 = - -------------------------------------------------------------------------------- - --- - ---------------------------------------------------------------------------------- 3 3*a _____________________________________________________________________ / ________________________________________ / / 2 3 / / / 3 \ / 2 \ / / |2*b 27*d 9*b*c| |b 3*c| / / |---- + ---- - -----| - 4*|-- - ---| / / | 3 a 2 | | 2 a | 3 / \/ \ a a / \a / b 27*d 9*b*c 3* / ----------------------------------------------- + -- + ---- - ----- 3 / 2 3 2*a 2 \/ a 2*a
_____________________________________________________________________ / ________________________________________ / / 2 3 / / / 3 \ / 2 \ / / |2*b 27*d 9*b*c| |b 3*c| / / |---- + ---- - -----| - 4*|-- - ---| / / | 3 a 2 | | 2 a | 3 / ___\ 2 / \/ \ a a / \a / b 27*d 9*b*c | 1 I*\/ 3 | b 3*c / ----------------------------------------------- + -- + ---- - ----- *|- - - -------| -- - --- 3 / 2 3 2*a 2 \ 2 2 / 2 a b \/ a 2*a a x_2 = - --- - ------------------------------------------------------------------------------------------------ - -------------------------------------------------------------------------------------------------- 3*a 3 _____________________________________________________________________ / ________________________________________ / / 2 3 / / / 3 \ / 2 \ / / |2*b 27*d 9*b*c| |b 3*c| / / |---- + ---- - -----| - 4*|-- - ---| / ___\ / / | 3 a 2 | | 2 a | 3 | 1 I*\/ 3 | / \/ \ a a / \a / b 27*d 9*b*c 3*|- - - -------|* / ----------------------------------------------- + -- + ---- - ----- \ 2 2 / 3 / 2 3 2*a 2 \/ a 2*a
_____________________________________________________________________ / ________________________________________ / / 2 3 / / / 3 \ / 2 \ / / |2*b 27*d 9*b*c| |b 3*c| / / |---- + ---- - -----| - 4*|-- - ---| / / | 3 a 2 | | 2 a | 3 / ___\ 2 / \/ \ a a / \a / b 27*d 9*b*c | 1 I*\/ 3 | b 3*c / ----------------------------------------------- + -- + ---- - ----- *|- - + -------| -- - --- 3 / 2 3 2*a 2 \ 2 2 / 2 a b \/ a 2*a a x_3 = - --- - ------------------------------------------------------------------------------------------------ - -------------------------------------------------------------------------------------------------- 3*a 3 _____________________________________________________________________ / ________________________________________ / / 2 3 / / / 3 \ / 2 \ / / |2*b 27*d 9*b*c| |b 3*c| / / |---- + ---- - -----| - 4*|-- - ---| / ___\ / / | 3 a 2 | | 2 a | 3 | 1 I*\/ 3 | / \/ \ a a / \a / b 27*d 9*b*c 3*|- - + -------|* / ----------------------------------------------- + -- + ---- - ----- \ 2 2 / 3 / 2 3 2*a 2 \/ a 2*a
sum
_____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ / ________________________________________ / ________________________________________ / ________________________________________ / / 2 3 / / 2 3 / / 2 3 / / / 3 \ / 2 \ / / / 3 \ / 2 \ / / / 3 \ / 2 \ / / |2*b 27*d 9*b*c| |b 3*c| / / |2*b 27*d 9*b*c| |b 3*c| / / |2*b 27*d 9*b*c| |b 3*c| / / |---- + ---- - -----| - 4*|-- - ---| / / |---- + ---- - -----| - 4*|-- - ---| / / |---- + ---- - -----| - 4*|-- - ---| / / | 3 a 2 | | 2 a | 3 2 / / | 3 a 2 | | 2 a | 3 / ___\ 2 / / | 3 a 2 | | 2 a | 3 / ___\ 2 / \/ \ a a / \a / b 27*d 9*b*c b 3*c / \/ \ a a / \a / b 27*d 9*b*c | 1 I*\/ 3 | b 3*c / \/ \ a a / \a / b 27*d 9*b*c | 1 I*\/ 3 | b 3*c / ----------------------------------------------- + -- + ---- - ----- -- - --- / ----------------------------------------------- + -- + ---- - ----- *|- - - -------| -- - --- / ----------------------------------------------- + -- + ---- - ----- *|- - + -------| -- - --- 3 / 2 3 2*a 2 2 a 3 / 2 3 2*a 2 \ 2 2 / 2 a 3 / 2 3 2*a 2 \ 2 2 / 2 a \/ a 2*a b a b \/ a 2*a a b \/ a 2*a a - -------------------------------------------------------------------------------- - --- - ---------------------------------------------------------------------------------- + - --- - ------------------------------------------------------------------------------------------------ - -------------------------------------------------------------------------------------------------- + - --- - ------------------------------------------------------------------------------------------------ - -------------------------------------------------------------------------------------------------- 3 3*a _____________________________________________________________________ 3*a 3 _____________________________________________________________________ 3*a 3 _____________________________________________________________________ / ________________________________________ / ________________________________________ / ________________________________________ / / 2 3 / / 2 3 / / 2 3 / / / 3 \ / 2 \ / / / 3 \ / 2 \ / / / 3 \ / 2 \ / / |2*b 27*d 9*b*c| |b 3*c| / / |2*b 27*d 9*b*c| |b 3*c| / / |2*b 27*d 9*b*c| |b 3*c| / / |---- + ---- - -----| - 4*|-- - ---| / / |---- + ---- - -----| - 4*|-- - ---| / / |---- + ---- - -----| - 4*|-- - ---| / / | 3 a 2 | | 2 a | 3 / ___\ / / | 3 a 2 | | 2 a | 3 / ___\ / / | 3 a 2 | | 2 a | 3 / \/ \ a a / \a / b 27*d 9*b*c | 1 I*\/ 3 | / \/ \ a a / \a / b 27*d 9*b*c | 1 I*\/ 3 | / \/ \ a a / \a / b 27*d 9*b*c 3* / ----------------------------------------------- + -- + ---- - ----- 3*|- - - -------|* / ----------------------------------------------- + -- + ---- - ----- 3*|- - + -------|* / ----------------------------------------------- + -- + ---- - ----- 3 / 2 3 2*a 2 \ 2 2 / 3 / 2 3 2*a 2 \ 2 2 / 3 / 2 3 2*a 2 \/ a 2*a \/ a 2*a \/ a 2*a
=
_____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ / ________________________________________ / ________________________________________ / ________________________________________ / / 2 3 / / 2 3 / / 2 3 / / / 3 \ / 2 \ / / / 3 \ / 2 \ / / / 3 \ / 2 \ / / |2*b 27*d 9*b*c| |b 3*c| / / |2*b 27*d 9*b*c| |b 3*c| / / |2*b 27*d 9*b*c| |b 3*c| / / |---- + ---- - -----| - 4*|-- - ---| / / |---- + ---- - -----| - 4*|-- - ---| / / |---- + ---- - -----| - 4*|-- - ---| / / | 3 a 2 | | 2 a | 3 2 / / | 3 a 2 | | 2 a | 3 / ___\ / / | 3 a 2 | | 2 a | 3 / ___\ 2 2 / \/ \ a a / \a / b 27*d 9*b*c b 3*c / \/ \ a a / \a / b 27*d 9*b*c | 1 I*\/ 3 | / \/ \ a a / \a / b 27*d 9*b*c | 1 I*\/ 3 | b 3*c b 3*c / ----------------------------------------------- + -- + ---- - ----- -- - --- / ----------------------------------------------- + -- + ---- - ----- *|- - + -------| / ----------------------------------------------- + -- + ---- - ----- *|- - - -------| -- - --- -- - --- 3 / 2 3 2*a 2 2 a 3 / 2 3 2*a 2 \ 2 2 / 3 / 2 3 2*a 2 \ 2 2 / 2 a 2 a \/ a 2*a b a \/ a 2*a \/ a 2*a a a - -------------------------------------------------------------------------------- - - - ---------------------------------------------------------------------------------- - ------------------------------------------------------------------------------------------------ - ------------------------------------------------------------------------------------------------ - -------------------------------------------------------------------------------------------------- - -------------------------------------------------------------------------------------------------- 3 a _____________________________________________________________________ 3 3 _____________________________________________________________________ _____________________________________________________________________ / ________________________________________ / ________________________________________ / ________________________________________ / / 2 3 / / 2 3 / / 2 3 / / / 3 \ / 2 \ / / / 3 \ / 2 \ / / / 3 \ / 2 \ / / |2*b 27*d 9*b*c| |b 3*c| / / |2*b 27*d 9*b*c| |b 3*c| / / |2*b 27*d 9*b*c| |b 3*c| / / |---- + ---- - -----| - 4*|-- - ---| / / |---- + ---- - -----| - 4*|-- - ---| / / |---- + ---- - -----| - 4*|-- - ---| / / | 3 a 2 | | 2 a | 3 / ___\ / / | 3 a 2 | | 2 a | 3 / ___\ / / | 3 a 2 | | 2 a | 3 / \/ \ a a / \a / b 27*d 9*b*c | 1 I*\/ 3 | / \/ \ a a / \a / b 27*d 9*b*c | 1 I*\/ 3 | / \/ \ a a / \a / b 27*d 9*b*c 3* / ----------------------------------------------- + -- + ---- - ----- 3*|- - + -------|* / ----------------------------------------------- + -- + ---- - ----- 3*|- - - -------|* / ----------------------------------------------- + -- + ---- - ----- 3 / 2 3 2*a 2 \ 2 2 / 3 / 2 3 2*a 2 \ 2 2 / 3 / 2 3 2*a 2 \/ a 2*a \/ a 2*a \/ a 2*a
product
_____________________________________________________________________ _____________________________________________________________________ _____________________________________________________________________ / ________________________________________ / ________________________________________ / ________________________________________ / / 2 3 / / 2 3 / / 2 3 / / / 3 \ / 2 \ / / / 3 \ / 2 \ / / / 3 \ / 2 \ / / |2*b 27*d 9*b*c| |b 3*c| / / |2*b 27*d 9*b*c| |b 3*c| / / |2*b 27*d 9*b*c| |b 3*c| / / |---- + ---- - -----| - 4*|-- - ---| / / |---- + ---- - -----| - 4*|-- - ---| / / |---- + ---- - -----| - 4*|-- - ---| / / | 3 a 2 | | 2 a | 3 2 / / | 3 a 2 | | 2 a | 3 / ___\ 2 / / | 3 a 2 | | 2 a | 3 / ___\ 2 / \/ \ a a / \a / b 27*d 9*b*c b 3*c / \/ \ a a / \a / b 27*d 9*b*c | 1 I*\/ 3 | b 3*c / \/ \ a a / \a / b 27*d 9*b*c | 1 I*\/ 3 | b 3*c / ----------------------------------------------- + -- + ---- - ----- -- - --- / ----------------------------------------------- + -- + ---- - ----- *|- - - -------| -- - --- / ----------------------------------------------- + -- + ---- - ----- *|- - + -------| -- - --- 3 / 2 3 2*a 2 2 a 3 / 2 3 2*a 2 \ 2 2 / 2 a 3 / 2 3 2*a 2 \ 2 2 / 2 a \/ a 2*a b a b \/ a 2*a a b \/ a 2*a a - -------------------------------------------------------------------------------- - --- - ---------------------------------------------------------------------------------- * - --- - ------------------------------------------------------------------------------------------------ - -------------------------------------------------------------------------------------------------- * - --- - ------------------------------------------------------------------------------------------------ - -------------------------------------------------------------------------------------------------- 3 3*a _____________________________________________________________________ 3*a 3 _____________________________________________________________________ 3*a 3 _____________________________________________________________________ / ________________________________________ / ________________________________________ / ________________________________________ / / 2 3 / / 2 3 / / 2 3 / / / 3 \ / 2 \ / / / 3 \ / 2 \ / / / 3 \ / 2 \ / / |2*b 27*d 9*b*c| |b 3*c| / / |2*b 27*d 9*b*c| |b 3*c| / / |2*b 27*d 9*b*c| |b 3*c| / / |---- + ---- - -----| - 4*|-- - ---| / / |---- + ---- - -----| - 4*|-- - ---| / / |---- + ---- - -----| - 4*|-- - ---| / / | 3 a 2 | | 2 a | 3 / ___\ / / | 3 a 2 | | 2 a | 3 / ___\ / / | 3 a 2 | | 2 a | 3 / \/ \ a a / \a / b 27*d 9*b*c | 1 I*\/ 3 | / \/ \ a a / \a / b 27*d 9*b*c | 1 I*\/ 3 | / \/ \ a a / \a / b 27*d 9*b*c 3* / ----------------------------------------------- + -- + ---- - ----- 3*|- - - -------|* / ----------------------------------------------- + -- + ---- - ----- 3*|- - + -------|* / ----------------------------------------------- + -- + ---- - ----- 3 / 2 3 2*a 2 \ 2 2 / 3 / 2 3 2*a 2 \ 2 2 / 3 / 2 3 2*a 2 \/ a 2*a \/ a 2*a \/ a 2*a
=
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