If `cosx=1/2(a+1/a)`, show that `cos2x=1/2(a^2+1/(a^2))`
997 views · Published 12 October 2018 · 1:21 · Indexed 4 October 2026
Channel: Doubtnut · 2018 · Education
To ask Unlimited Maths doubts download Doubtnut from - https://goo.gl/9WZjCW If `cosx=1/2(a+1/a)`, show that `cos2x=1/2(a^2+1/(a^2))`
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