Question

Xв четвертой степени ---13xво второй степени +36=0

Answer 1

х^2=a

a^2 - 13a + 36 = 0

a1 = 9

a2 = 4

x^2= 9                                x^2 = 4

x1 = 3                                 x3 = 2

x2 = -3                                 x4= - 2

Answer 2

 обозначим  x^2=у    

y^2-13y+36=0

D=169-144=25

y1=4

y2=9

 

x^2=4               x^2=9  

x1=2                 x3=3

x2=-2                x4=-3