Integrate cos(4x)+16x^3 with respect to x

This is a simple integration, integrating each individual term with respect to x.For the cos(4x), you should use 'integration by substitution' as it is a function of a function.cos(4x) = cos(u) and u = 4x where dx/du = 4, so dx = (1/4)duso we are now integrating: (1/4)cos(u) duthe 1/4 is a constant so can be taken infront---> integrates to sin(u)The integration of cos(u) is sin(u), using the memorised circle that can be used below:Down is differentiation, up is integration sinxcosx -sinx-cosx (then back to sinx and repeat)so (sin(u))/4and u = 4x so answer is sin(4x)/4Integrating the second value, by adding a power then dividing by the new power:16x^3 becomes (16x^4)/4 = 4x^4So finally, the solution is:sin(4x)/4+ 4x^4+Constant

AC

Related Maths A Level answers

All answers ▸

Why is the definite integral between negative limits of a function with positive values negative even though the area bound by the x-axis is positive? for example the integral of y=x^2 between x=-2 and x=-1


Find the turning point of the line y = x^2 + 2x -1


A ball is projected vertically upwards from the ground with speed 21 ms^–1. The ball moves freely under gravity once projected. What is the greatest height reached by the ball?


Integral of a compound equation (or otherwise finding the area under a graph): f(x) = 10x*(x^(0.5) - 2)