-2x^2-5x-2=0 *(-1)
2x^2+5x+2=0
D=25-16=9
x1=(-5-3)/4=-8/4=-2
x2=(-5+3)/4=-2/4=-0.5
1) =(sinb/cosb+1)/(cosb/sinb+1)= (sinb+cosb)/cosb):(sinb+cos b)/sinb=
=(sinb+cosb)/cosb)*(sinb/(sinb+cosb)=sinb/cosb=tgb
2) =²a+2sinacosa+cos²a-2sina* cosa=sin²a+cos²a=1
3)=(sin²a+cos²a)²=1
4) =2-(sin²a+cos²a)/3(sin²a+cos²a)=2-1/3*1=1/3
5) = (sin²a-cos²a)(sin²a+cos²a)/sin²a-cos²a)=sin²a+cos²a=1
Х=+-11…………….…………………………………………………….