1) t^2+6t+9=0 2) z^4=4z^2 3) x^2-8x+16=0 4) t^5=9t^3 решите уравнения

1) а) t^2 +6t +9 =0 

D = b^2 -4ac = 36-36= 0 - 1 корень

t = -b/2a = -6/2 = -3

б) t^2 +6t +9 =0 

(t+3)^2 = 0

t+3 = 0

t = -3

2) z^4=4z^2

z^4 - 4z^2 = 0

z^2 * (z^2 - 4) = 0

z^2=0    или  z^2 - 4 = 0

z=0                  z^2 = 4

                         z = +-2

3) а) x^2 - 8x + 16 = 0

D = b^2 - 4ac = 64 - 16*4 = 64 - 64 = 0 - 1 корень 

x = -b/2a = 8/2 = 4

б) x^2 - 8x + 16 = 0

(x+4)^2 = 0

x+4 = 0 

x = -4

4) t^5 = 9t^3

t^5 - 9t^3 = 0

t^3 * (t^2 - 9) = 0

t^3 = 0 или  t^2 - 9 = 0

t = 0                t^2 = 9

                        t = +-3

Удачи!