Question

Тригонометрия...упростите.

Answer 1

(1+2cos²2a-1+2sin2acos2a)/(1-1+2sin²2a+2sin2acos2a)-ctg2a=
=(2cos²2a+2sin2acos2a)/(2sin²2a+2sin2acos2a)-ctg2a=
=2cos2a(cos2a+sin2a)/2sin2a(sin2a+cos2a)-ctg2a=
=cos2a/sin2a-ctg2a=ctg2a-ctg2a=0

(sin²2a+4(sin²a-1))/(2sin²2a-8sin²a)-1/2*ctg^4a=
=(4sin²acos²a-4cos²a)/(8sin²acos²a-8sin²a)-1/2*ctg^4a=
=4cos²a(sin²a-1)/8sin²a(cos²a-1)-1/2*ctg^4a=
=-4cos^4a/(-8sin^4a)-1/2*ctg^4a=1/2*ctg^4a-1/2*ctg^4a=0