Question

решите пж с решением а,б,в,г

Answer 1

$1) frac{sin^2t}{1+cost} = frac{1-cos^2t}{1+cost} =frac{(1-cost)(1+cost)}{1+cost}=1-cost \ 2) sin^4t+cos^4t+2sin^2tcos^2t=(sin^2t+cos^2t)^2=1^2=1 \ 3) frac{cos^2t}{1+sint}+sint=frac{1-sin^2t}{1+sint}+sint=frac{(1-sint)(1+sint)}{1+sint}+sint= \ =1-sint+sint=1 \ 4)cos^4t+cos^2tsin^2t-cos^2t+1=cos^2t(cos^2t+sin^2t-1)+1= \ =cos^2t(1-1)+1=1$