Question

已知函数f(x)=3x^2-5x+2,求f(-根号2），f(-a),f(a+3),f(a)+f(3)

后面还有“的值”二字

Answer 1

代入方程得：f(-根号2）=8+5根号2
f(-a)=3a^2+5a+2
f(a+3)=3a^2+13a+14
f(a)+f(3)=3a^2-5a+16

Answer 2

f(-√2）=8+5√2
f(-a)=3a^2+5a+2
f(a+3)=(a+3)^2-5(a+3)+2
f(a)+f(3)=(3a^2-5a+2)+14=3a^2-5a+16