I need help with math!!!

[vanesa0123]

I need to prove that these two equations are the same, but i dont know how to even begin. This is the equation:
(sin^3x-cos^3x)/(sinx-cosx)=(2+sin2x)/2
how do i do this? HELP!

 

[Deleted member 4993]

I need to prove that these two equations are the same, but i dont know how to even begin. This is the equation:
(sin^3x-cos^3x)/(sinx-cosx)=(2+sin2x)/2
how do i do this? HELP!

Start with Left-hand-side and factorize the numerator using:

a³ - b³ = (a - b)(a² + ab + b²)

continue after that.....


Please share your work with us indicating exactly where you are stuck - so that we may know where to begin to help you.

 

[dsk2]

vanesa0123,


I am sure with Subhotosh Khan's suggestion, you are done solving the solution I hope.

No reason to get stuck, but if you are, you will need to use the following two identities:

\(\displaystyle sin^2(x)+cos^2(x)=1\) and
\(\displaystyle sin(2x)=2sin(x)cos(x)\)

Cheers,
Sai.