(x+2)(x+3)(x+8)(x+12)≤4x²
(x²+3x+2x+6)(x²+12x+8x+96)≤4x²
(x²+5x+6)(x²+20x+96)≤4x²
x⁴+20x³+96x²+5x³+100x²+480x+6x²+120x+576≤4x²
(x⁴)+(20x³+5x³)+(96x²+100x²+6x²-4x²)+(480x+120x)+576≤0
x⁴+25x³+198x²+600x+576≤0
x=-4
x⁴+25x³+198x²+600x+576|x+4
x⁴+4x³ x³+21x²+114x+144
21x³+198x²+600x+576
21x³+84x²
114x²+600x+576
114x²+456x
144x+576
144x+576
0
(x+4)(x³+21x²+114x+144)≤0
x³+21x²+114x+144=0
x=-6
x³+21x²+114x+144|x+6
x³+6x² x²+15x+24
15x²+114x+144
15x²+90x
24x+144
24x+144
0
(x+4)(x+6)(x²+15x+24)≤0
x²+15x+24=0
D=15²-4*24=225-96=129
x₁=(-15+√129)/2
x₂=(-15-√129)/2
(x+4)(x+6)(x-((-15+√129)/2))(x-((-15-√129)/2))≤0
√121<√129<√144 ⇒ 11<√129<12 ⇒ √129≈11,3
(-15+11,3)/2=-1,85
(-15-11,3)/2=-13,15
//////////////// ////////////////
+ - + - +
________.________.________.________.________
(15-√129)/2 -6 -4 (-15+√129)/2
x∈[(15-√129)/2;-6]U[-4;(-15+√129)/2]
(4х + 3)(х-1) - (3х - 2)(х+2) = 10 - 5х
4х * х + 4х * (-1) + 3*х +3*(-1) - (3х*х + 3х*2 - 2*х -2*2) = 10 - 5х
4х² - 4х + 3х - 3 - (3х² + 6х - 2х - 4) = 10 - 5х
4х² - х - 3 - 3х² - 4х + 4 = 10 - 5х
х² - 5х + 1 = 10 - 5х
х² - 5х + 1 - 10 + 5х = 0
х² - 9 = 0
х² - 3² = 0
(х - 3)(х +3) = 0
х - 3= 0
х₁ = 3
х + 3 = 0
х₂ = - 3
√2(-√3-√5+√2)/√5(√2-√5-√3)=√2/√5=√10/5