Show that: `cotx-cot2x=2` – InterviewSolution

InterviewSolution

1.	Show that: `cotx-cot2x=2`
Answer» `L.H.S. = cotx - cot2x = cosx/sinx -(cos2x)/(sin2x)` `=(cosxsin2x - cos2xsinx)/(sinxsin2x)` `=(sin(2x-x))/(sinxsin2x) = sinx/(sinxsin2x)` When, `x = 15^@` `1/(sin2x) = 1/(sin30^@) = 2 = R.H.S.` So, given equation is true for `x = 15^@`

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