Question

Dada a função: f(x)= -x²+5x+6, calcule:

A) f (-1)
B) x para f(x)=0

Answer 1

A) f (-1) =-(-1)²+5*(-1)+6 =-1-5+6= -6+6=0


B) x para f(x)=0

-x²+5x+6=0

x²-5x-6=0

x'=[5+√(25+24)]/2=(5+7)/2=6

x''=[5-√(25+24)]/2=(5-7)/2=-1