1) t4-1/5t2+1/100=0

2) (2z2+11z) 2-23 (2z2+11z) + 126=0

3) (x2-4x+1) (x2-4x+2) = 12

2) пусть 2z^2 + 11z = a

a^2 - 23a + 126=0

a = 9 a = 14

2z^2 + 11z = 9

2z^2 + 11z-9 = 0

z = - 4,5 z = 1

2z^2 + 11z = 14

2z^2 + 11z - 14 = 0

z = - 3.5 z = - 2

3) x^2 - 4x = a

(a+1) (a+2) = 12

a^2 + 3a + 2 = 12

a^2 + 3a - 10 = 0

a = 2 a = - 5

x^2 - 4x = 2

x^2 - 4x - 2 = 0

x^2 - 4x = - 5

x^2 - 4x + = 0