How do you integrate 3(1x2)dx using trigonometric substitution?

1 Answer
Apr 5, 2016

3(1x2)dx=34sin2θ+32θ+C

Explanation:

x=sinθ,dx=cosθdθ

3(1sin2θ)cosθdθ=3(cos2θ)cosθdθ

=3cosθcosθdθ

=3cos2θdθ

=312(cos2θ+1)dθ

=32(cos2θ+1)dθ

=32[12sin2θ+θ]

=34sin2θ+32θ+C