If f(x)=x^2 + 2x +3f(x)=x2+2x+3, then how do you find f(a-1)?
2 Answers
May 28, 2016
Explanation:
Substitute x = a-1 into function.
rArrf(a-1)=(a-1)^2+2(a-1)+3⇒f(a−1)=(a−1)2+2(a−1)+3 expand brackets and collect like terms.
rArr(a-1)^2+2(a-1)+3=a^2-2a+1+2a-2+3⇒(a−1)2+2(a−1)+3=a2−2a+1+2a−2+3
=a^2+2=a2+2
May 28, 2016
It is enough to substitute
Explanation:
It is enough to write
then it is just a matter of doing a bit of algebra