Question

Dada a função f:IR--->IR definida por f(x)=x²-x-12, determine a para que f(a+1)=0.

Answer 1

f(X)=X²-X-12
f(a+1)=0

f(a+1)=(a+1)²-(a+1)-12
0=(a+1)²-(a+1)-12
0=a²+2a+1-a-1-12
0=a²+a-12
a²+a-12=0

tirando as raizes com baskaras a=3 ou a= -4