Question

For the function f(x)=3xsquared- 2x+5 find f(1) f(-2) and f(a)

Answer 1

$f(x)=3x^2-2x+5\\\\ f(1):\ \ Substitude\ 1 \ as\ x\ into\ function:\\ f(1)=3*1^2-2*1+5=3-2+5=\textbf{6}\\\\ f(-2)\ \ Substitude\ x=-2\\ f(-2)=3*(-2)^2-2*(-2)+5=3*4+4+5=12+4+5=\textbf{21}\\\\ f(a)\ \ substitude\ x=a\\ f(a)=\underline{3a^2-2a+5}$