The points at which the function is not precisely defined: x1=0 x2=3.14159265358979
The points of intersection with the X-axis coordinate
Graph of the function intersects the axis X at f = 0 so we need to solve the equation: sin(x)cos(x)=0 Solve this equation The points of intersection with the axis X:
The points of intersection with the Y axis coordinate
The graph crosses Y axis when x equals 0: substitute x = 0 to cos(x)/sin(x). sin(0)cos(0) The result: f(0)=∞~ sof doesn't intersect Y
Extrema of the function
In order to find the extrema, we need to solve the equation dxdf(x)=0 (the derivative equals zero), and the roots of this equation are the extrema of this function: dxdf(x)= the first derivative −1−sin2(x)cos2(x)=0 Solve this equation Solutions are not found, function may have no extrema
Inflection points
Let's find the inflection points, we'll need to solve the equation for this dx2d2f(x)=0 (the second derivative equals zero), the roots of this equation will be the inflection points for the specified function graph: dx2d2f(x)= the second derivative sin(x)(2+sin2(x)2cos2(x))cos(x)=0 Solve this equation The roots of this equation x1=2π x2=23π You also need to calculate the limits of y '' for arguments seeking to indeterminate points of a function: Points where there is an indetermination: x1=0 x2=3.14159265358979
x→0−limsin(x)(2+sin2(x)2cos2(x))cos(x)=−∞ Let's take the limit x→0+limsin(x)(2+sin2(x)2cos2(x))cos(x)=∞ Let's take the limit - the limits are not equal, so x1=0 - is an inflection point x→3.14159265358979−limsin(x)(2+sin2(x)2cos2(x))cos(x)=−1.08892367577758⋅1048 Let's take the limit x→3.14159265358979+limsin(x)(2+sin2(x)2cos2(x))cos(x)=−1.08892367577758⋅1048 Let's take the limit - limits are equal, then skip the corresponding point
Сonvexity and concavity intervals: Let’s find the intervals where the function is convex or concave, for this look at the behaviour of the function at the inflection points: Concave at the intervals (−∞,2π] Convex at the intervals [23π,∞)
Vertical asymptotes
Have: x1=0 x2=3.14159265358979
Horizontal asymptotes
Let’s find horizontal asymptotes with help of the limits of this function at x->+oo and x->-oo x→−∞lim(sin(x)cos(x))=⟨−∞,∞⟩ Let's take the limit so, equation of the horizontal asymptote on the left: y=⟨−∞,∞⟩ x→∞lim(sin(x)cos(x))=⟨−∞,∞⟩ Let's take the limit so, equation of the horizontal asymptote on the right: y=⟨−∞,∞⟩
Inclined asymptotes
Inclined asymptote can be found by calculating the limit of cos(x)/sin(x), divided by x at x->+oo and x ->-oo x→−∞lim(xsin(x)cos(x))=x→−∞lim(xsin(x)cos(x)) Let's take the limit so, inclined asymptote equation on the left: y=xx→−∞lim(xsin(x)cos(x)) x→∞lim(xsin(x)cos(x))=x→∞lim(xsin(x)cos(x)) Let's take the limit so, inclined asymptote equation on the right: y=xx→∞lim(xsin(x)cos(x))
Even and odd functions
Let's check, whether the function even or odd by using relations f = f(-x) и f = -f(-x). So, check: sin(x)cos(x)=−sin(x)cos(x) - No sin(x)cos(x)=sin(x)cos(x) - No so, the function not is neither even, nor odd