Q10 of 104 Page 188

If tanA = √3, verify that

(1) sin2A + cos2A = 1


(2) sec2A – tan2A = 1


(3) 1 + cot2A = cosec2A


Let BC = √3 and AC = 1


⇒ AB = 2 (by Pythagoras theorem)


we know that





⇒


⇒


⇒


⇒


⇒


(1) sin2A + cos2A = 1


⇒


(2) sec2A – tan2A = 1


⇒


(3) 1 + cot2A = cosec2A


⇒ L.H.S


⇒


R.H.S


⇒


L.H.S = R.H.S

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