can u help me solve this question

If xcos θ + y sinθ = a cos 2θ and;

xsinθ - ycos θ = 2a sin 2θ

prove that (x+y)2/3 + (x-y)2/3 = 2a2/3

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- Jun 12th 2007, 02:22 AMcalculus_jyhard!
can u help me solve this question

If xcos θ + y sinθ = a cos 2θ and;

xsinθ - ycos θ = 2a sin 2θ

prove that (x+y)2/3 + (x-y)2/3 = 2a2/3 - Jun 12th 2007, 05:56 AMSoroban
Hello, calculus_jy!

This is*The Problem from Hell*. . . (coming to a theater near you)

Quote:

If .

prove that: .

Multiply [2] by

Add: .

. . . .

. . . . . . . . . . . . .

. . . . . . . . . . . . .

In a similar fashion solve for

We have: .

. . . . . . . . . . . .

. . . . . . . . . . . .

We have: .

. . . . . . . . . . . .

. . . . . . . . . . . .

Then: .

Add [3] and [4]:

. .

. . . . . . . . . . . . . .

. . . . . . . . . . . . . .

. . . . . . . . . . . . . .

Therefore: . . . . . ta-*DAA!!*

- Jun 12th 2007, 11:45 PMcalculus_jyGreat thx
i really appreciate ur help, and u said it is a problem from hell, just wondering how u manage to start solving problems lyk this, besides practicing and using ur brain, can u offer me few tips??

Also i hav 2 other problems from hell, i will post it in the geometry section and wonder if u can help me with them, they took me ages!