Question

prove sin^2+cos^2=1
in brief 3 marks

Answer 1

this is my friend solution in brief

Answer 2

⇒$Sin = \frac{perpendicular}{hypotenuse}$

⇒$Sin^2 = \frac{perpendicular^2}{hypotenuse^2}$

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⇒$Cos = \frac{base}{hypotenuse}$

⇒$Cos^2 = \frac{base^2}{hypotenuse^2}$

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Now,

sin² +  cos²

⇒$\frac{height^2}{hypotenuse^2} + \frac{base^2}{hypotenuse^2}$

⇒$\frac{height^2 + base^2}{hypotenuse^2}$

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By Pythagoras theorem,
base² + height² = hypotenuse²
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⇒$\frac{height^2 + base^2}{hypotenuse^2}$

⇒$\frac{hypotenuse^2}{hypotenuse^2}$

⇒1 

Hence, Proved.


i hope this will help you


-by ABHAY