Prove that #(1+sin2A+cos2A)/(1+sin2A-cos2A)=cotA#?

1 Answer
Jim H · Shwetank Mauria
Nov 26, 2017

I assume that there are parentheses missing from the question and that it should be

Prove that #(1+sin2A+cos2A)/(1+sin2A-cos2A)=cotA#

Use #sin2A = 2sinAcosA# and

#cos2A = 1-2sin^2A# and #cos2A = 2cos^2A-1#

#(1+sin2A+cos2A)/(1+sin2A-cos2A) = (1+2sinAcosA+2cos^2A-1)/(1+2sinAcosA-(1-2sin^2A))#

# = (2cosA(sinA+cosA))/(2sinA(cosA+sinA))#

# = cosA/sinA#

# = cotA#

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