Let's take the limit x→1+lim(x−15−5x) Multiply numerator and denominator by −x−1 we get (−x−1)(x−1)(5−5x)(−x−1) = 1−x5(1−x)(−x−1) = −5x−5 The final answer: x→1+lim(x−15−5x) = x→1+lim(−5x−5) = −10
Lopital's rule
We have indeterminateness of type
0/0,
i.e. limit for the numerator is x→1+lim(5−5x)=0 and limit for the denominator is x→1+lim(x−1)=0 Let's take derivatives of the numerator and denominator until we eliminate indeterninateness. x→1+lim(x−15−5x) = Let's transform the function under the limit a few x→1+lim(x−15(1−x)) = x→1+lim(dxd(x−1)dxd(5−5x)) = x→1+lim(−10x) = x→1+lim−10 = x→1+lim−10 = −10 It can be seen that we have applied Lopital's rule (we have taken derivatives with respect to the numerator and denominator) 1 time(s)