а )х ^ 2 - 6 | х | + 5 = 0 ; 1 ) x ^ 2 - 6 * x + 5 = 0 ; D = b ^ 2 - 4ac = (-6) ^ 2 - 4·1·5 = 36 - 20 = 16 ;x1 = ( 6 - √16 ) / ( 2 · 1 ) = ( 6 - 4 ) / 2 = 2 / 2 = 1 ;x2 = ( 6 + √16 ) / ( 2 · 1 ) = ( 6 + 4 ) / 2 = 10 / 2 = 5 ; 2 ) x ^ 2 + 6 * x + 5 = 0 ; D = b ^ 2 - 4ac = 6 ^ 2 - 4·1·5 = 36 - 20 = 16 ;x1 = ( -6 - √16 ) / ( 2·1 ) = ( -6 - 4 ) / 2 = -10 / 2 = -5;x2 = ( -6 + √16 ) / ( 2·1 ) = ( -6 + 4 ) / 2 = -2 / 2 = -1;б )( 2 * х - 1 ) ^ 4 - (2х-1) ^ 2 -12=0 ; Пусть ( 2 * x - 1 ) ^ 2 = a, тогда: a ^ 2 - a - 12 = 0 ; a = - 3 ; a = 4 ; Тогда:1 ) ( 2 * x - 1 ) ^ 2 = - 3 ; Нет корней ; 2 ) ( 2 * x - 1 ) ^ 2 = 4 ; 2 * x - 1 = + - 2 ; 2 * x - 1 = 2 , 2 * x = 3 , x = 1.5 ; 2 * x - 1 = - 2 , 2 * x = - 1 , x = - 0.5.