Question

prove that sin^2A + cos^2A = 1
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Answer 1

Question :

Prove that sin²A + cos²A = 1 .

Proof :

We know that ,

According to Pythagoras theorem ,

p² + b² = h² ---------(1)

where ,

p = perpendicular

b = base

h = hypotenuse

Now ,

Dividing both sides of eq-(1) by h² ,

We get ;

=> (p² + b²)/h² = h²/h²

=> p²/h² + b²/h² = 1

=> (p/h)² + (b/h)² = 1

=> sin²A + cos²A = 1

Hence proved .