(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

If A is an acute angle and sinA = cosA

Find the value of 2 tan^{2}A+ sin^{2 }A-1

2. Relevant equations

3. The attempt at a solution

I well tried this way >>

2 (sin^{2}A/cos^{2}A) +sin 2 A-1

= 1+ cos^{2 }A

But I am unable to get the 'value' the answer given in the book is 3/2.

Can anybody please suggest any way by which I can get a proper value ?

I would be very thankful!

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# Homework Help: Trig sum

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