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Magical Mathematics[Interesting Approach]> tantheta=b/athen prove that acos2theta+bs...

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tantheta=b/athen prove that acos2theta+bsin2theta=a

abhinav , 10 Years ago

Grade 11

1 Answers

Riddhish Bhalodia

ok I hope you are familier with the following two identities
$cos2\theta = \frac{1-tan^2\theta}{1+tan^2\theta} , sin2\theta = \frac{2tan\theta}{1+tan^2\theta}$
now its just the question of using thes two and substituting
$tan\theta = b/a$
in the equation and you will get the answer very easily

Last Activity: 10 Years ago

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