Integration Qu with sin²x stuff. (1 Viewer)

[currysauce]

Write down an expression for sin3x in terms of sinx.

i did that

3 sinx -4 sin^3x


Next part says, hence fine INTEGRAL (from pi/6 to 0) sin^3 x dx

thanks

 

[Slidey]

Write down an expression for sin3x in terms of sinx.

i did that

3 sinx -4 sin^3x


Next part says, hence fine INTEGRAL (from pi/6 to 0) sin^3 x dx

thanks

sin3x=3sinx-4sin^3(x)
.'. sin^3(x)=(3sinx-sin3x)/4

So integral of sin^3(x) = integral of (3sinx-sin3x)/4
= {cos3x-9cosx}/12

 

[currysauce]

thanks man, i got it