Question #78a09
1 Answer
Feb 26, 2017
Well, recall that:
#tanx = sinx/cosx# #cotx = 1/tanx = cosx/sinx# #sin^2x + cos^2x = 1# #csc^2x = 1/sin^2x#
Thus:
#cot^2x(1+tan^2x)#
#= cos^2x/sin^2x(1+sin^2x/cos^2x)#
#= cos^2x/sin^2x + 1#
#= (cos^2x + sin^2x)/(sin^2x)#
#= 1/sin^2x#
#= color(blue)(csc^2x)#
