Question

Ajutor la 10 și 13 a. Ms

Answer 1

(f°f)(x)=f(f(x))=a*f ² (x)+b=a(ax²+b)²+b=a(a²x^4+2abx²+b²)+b=a(ax²+b)²+b=
a³x^4+2a²bx²+ab²+b=8*x^4
a³=8 ⇒a=2
b=0

Ex. 13. a)
(f°f)(x)=f(f(x))=m*f(x)-3=m(mx-3)-3=m²x-3m-3
m²x-3m-3=4x+3
m²=4, m1=2, m2=-2
-3m-3=3
-3m=6
m=-2 Solutie.