SOLUTION: prove the identity: a) cot((x+pi)/(2)) = -tanx b) tanx = (1 - cos2x)/ (sin2x)

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Question 1155757: prove the identity:
a) cot((x+pi)/(2)) = -tanx
b) tanx = (1 - cos2x)/ (sin2x)

Answer by MathLover1(20850)   (Show Source): You can put this solution on YOUR website!
prove the identity:
a) It was supposed to be cot(x + pi/2)

manipulate left side
.........use identities: , and

= ....since ,

=
=
=

so,


b)


manipulate right side:


use the following identity:
and

=

=

=......simplify

=

=

=



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