(1/4)*x²+x=0
x((1/4)x+1)=0
x₁=0 x₂=-4.
sinx^2=1-cosx^2=1-0.36=0.64 sinx=-0.8 sinx=0.8
sinx^2=1-0=1 sinx=-1 sinx=1
tgx=3/4 cosx^2=1/(1+tgx^2)=1/(1+9/16)=1/(25/16) cosx^2=16/25 cosx=-4/5 cosx=4/5 2cosx=-8/5 2cosx=8/5
tgx=pi cos^2x=1/1+0=1 cosx^2=1 cosx=+-1 2cosx=+-2
1)350 000\ 420 000=0,833
2)0,833*100%=83,3%,т.е. 83%