4.已知函数f(x) =3x²-5x+2,求f(a)+f(3)的值

4.已知函数f(x) =3x²-5x+2,求f(a)+f(3)的值
4.已知函数f(x) =3x²-5x+2,求f(a)+f(3)的值

4.已知函数f(x) =3x²-5x+2,求f(a)+f(3)的值
f(a)=3a^2-5a+2,f(3)=3*3^2-5*3+2=27+2-15=14
所以f(a)+f(3)=3a^2-5a+2+14=3a^2-5a+16