1)(8x+1)(2x--2)^2=1 2)x^3-144x=0 3)x^4-10x^2+9=0

1) (8х + 1)(2х - 3) - (4х - 2)^2 - 1 = 0 16х^2 - 24x + 2x - 3 - (16x^2 - 16x + 4) - 1 = 0 16x^2 - 24x + 2x - 3 - 16x^2 + 16x - 4 - 1 = 0 10x - 8 = 0 10x = 8 x = 0,8 2) x^3 - 144x = 0 x (x^2 - 144) = 0 а)  x = 0; б) x^2 = 144 x = 12; -12 3) x^4 - 10x^2 + 9 = 0 x^2 = t t^2 - 10t + 9 = 0 d1 = 25 - 9 = 16; корень из d1 = 4 t1 = 5 + 4 = 9; t2 = 5 - 4 = 1 a) x^2 = 9 x = 3; -3 б) x^2 = 1 x = 1; -1

скорость лодки -х,тогда

90/(х+2)+44/(х-2)=10

90x-180+44x+88=10x^2-40

10x^2-134x+52=0

5x^2-67x+26=0

x=13