Question #5adb3

1 Answer
Sep 20, 2016

Alternative I :-

-{2cosx+ln|cscx-cotx|+C.{2cosx+ln|cscxcotx|+C.

Alternative II :-

1/4(2x-sin2x)-ln|cscx-cotx|-cosx+C14(2xsin2x)ln|cscxcotx|cosx+C

Explanation:

Though the Question is not clear, but we solve it by taking 22 possibilities :

Alternative I :-

int(sin^2x-cos^2x)/sinx dx=int{(sin^2x-(1-sin^2x)}/sinxdxsin2xcos2xsinxdx={sin2x(1sin2x)sinxdx

=int(2sin^2x-1)/sinx dx=int{(2sin^2x)/sinx-1/sinx}dx=2sin2x1sinxdx={2sin2xsinx1sinx}dx

=2intsinxdx-intcscxdx=2sinxdxcscxdx

=2(-cosx)-ln|cscx-cotx|=2(cosx)ln|cscxcotx|

=-{2cosx+ln|cscx-cotx|+C.={2cosx+ln|cscxcotx|+C.

Alternative II :-

int{sin^2x-cos^2x/sinx}dx{sin2xcos2xsinx}dx

We use the Identity : sin^2x=(1-cos2x)/2:sin2x=1cos2x2.

:. int{sin^2x-cos^2x/sinx}dx

=int(1-cos2x)/2dx-int(1-sin^2x)/sinxdx

1/2(x-sin(2x)/2)-int(1/sinx-sinx)dx

=1/4(2x-sin2x)-intcscxdx+intsinxdx

=1/4(2x-sin2x)-ln|cscx-cotx|-cosx+C

Enjoy Maths.!