Then put the first three into a 'perfect square'.

Bob

]]>add and subtract the term

Like this?

I will do these as soon as possible

]]>exercise for you: do a similar thing with b^3

evaluate a/b and b/a and substitute all into (1)

everything cancels leaving just a 1

Bob

]]>cancel and put over common denominator

add and subtract the term

make use of

Bob

stereogram answer on the other thread

]]>I had almost forgotten about the stereograms. What did you figure out about it?

]]>Starting with

That looks like a good way to start with those denominators. Then put everything in terms of sin and cos in order to simplify.

The second identity looks somewhat tougher. I'll come back if I make progress.

Bob

ps. I've made some progress with stereograms.

]]>1.

2. If cosec θ - sin θ = a[sup]3[/sup] and sec θ - cos θ = b[sup]3[/sup], Then prove that: a²b²(a² + b²) = 1

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