Cot x/ tan x × sec²x = cosec x how? prove it

1 Answer
May 10, 2018

We have;

#(cosx/sinx)/(sinx/cosx) xx 1/cos^2x = 1/sinx#

#cos^2x/sin^2x xx 1/cos^2x = 1/sinx#

#1/sin^2x = 1/sinx#

This is clearly FALSE so the identity cannot be proved. We can confirm graphically.

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Since the two curves don't lie directly on each other, the given expression is an equation not an identity.

Hopefully this helps!