F(x)=2x² / (1-7x )
F'= ((4х·(1-7х)+14х²)) / (1-7х)²
Х=(1-6)/1/10, х= -5*10, х=-50
Sin(π - t) + cos(3π/2 + t) > - √3
sint + sint > - √3
2sint > - √3
sint > - √3/2
arcsin(-√3/2) + 2πn < t < π - arcsin(-√3/2) + 2πn, n∈Z
-π/3 + 2πn < t < π -( - π/3) + 2πn, n∈Z
-π/3 + 2πn < t < (4π/3) + 2πn, n∈Z