D(F)=x² * √x = (f'g+fg')=((x²)'√x + x^2(x^1/2)')=2x*√x+x^2*1/2√x = 5√x³/2
(сos²t-sin²t)/(cost-sint)=(cost-sint)(cost+sint)/(cost-sint)=cost+sint
2
2x²-3x+1>2x-2
2x²-5x+3>0
D=25-24=1
x1=(5-1)/4=1 U x2=(5+1)/4=1,5
x∈(-∞;1 ) U (1,5;∞)
3
x²+6x-3(2x+3)≤12*6
x²+6x-6x-9-72≤0
x²-81≤0
(x-9)(x+9)≤0
x=-9 x=9
x∈[-9;9]
4
(x-3)²-4(x-2)²≤8(1-x)
x²-6x+9-4x²+16x-16-8+8x≤0
-3x²+18x-15≤0
x²-6x+5≥0
x1+x2=6 U x1*x2=5
x1=1 U x2=5
x∈(-∞;1] U [5;∞)