Question

Cho hàm số y=f(x) = 3x² + 1 .Tính: f 1/2 ; f(1) ; f(3)cần gấp

Answer 1

Ta có: f(1/2)=3.1/2^2+1=1,75

f(1)=3.1^2+1= 4

f(3)=3.3^2+1=38

Answer 2

Ta có : \(y=f\left(x\right)=3x^2+1\)

\(+\)

\(f\left(\frac{1}{2}\right)=3.\left(\frac{1}{2}\right)^2+1=\frac{7}{4}\)

\(+\)

\(f\left(1\right)=3.\left(1\right)^2+1=4\)

\(+\)

\(f\left(3\right)=3.\left(3\right)^2+1=28\)

Answer 3

f (1/2) = 3. (1/2)² +1 =3.1/4 +1= 3/4 +1 =1 3/4

f (1) = 3.(1)² +1= 3.1+1=3+1 =4

f(3) = 3.(3)² -1= 3.9+1=27+1=28