Answer :
We are given the function
[tex]$$
f(x)=3x^2+2x-1.
$$[/tex]
We need to find the value of [tex]$f(5)$[/tex] by substituting [tex]$x=5$[/tex] into the function.
Step 1: Substitute [tex]$x=5$[/tex] into the function:
[tex]$$
f(5)=3(5)^2+2(5)-1.
$$[/tex]
Step 2: Compute [tex]$(5)^2$[/tex]:
[tex]$$
(5)^2=25.
$$[/tex]
Step 3: Multiply by 3:
[tex]$$
3(25)=75.
$$[/tex]
Step 4: Multiply 2 by 5:
[tex]$$
2(5)=10.
$$[/tex]
Step 5: Combine the results:
[tex]$$
f(5)=75+10-1.
$$[/tex]
Step 6: Calculate the final value:
[tex]$$
75+10=85,
$$[/tex]
[tex]$$
85-1=84.
$$[/tex]
Thus, the value of [tex]$f(5)$[/tex] is [tex]$\boxed{84}$[/tex], which corresponds to option B.
[tex]$$
f(x)=3x^2+2x-1.
$$[/tex]
We need to find the value of [tex]$f(5)$[/tex] by substituting [tex]$x=5$[/tex] into the function.
Step 1: Substitute [tex]$x=5$[/tex] into the function:
[tex]$$
f(5)=3(5)^2+2(5)-1.
$$[/tex]
Step 2: Compute [tex]$(5)^2$[/tex]:
[tex]$$
(5)^2=25.
$$[/tex]
Step 3: Multiply by 3:
[tex]$$
3(25)=75.
$$[/tex]
Step 4: Multiply 2 by 5:
[tex]$$
2(5)=10.
$$[/tex]
Step 5: Combine the results:
[tex]$$
f(5)=75+10-1.
$$[/tex]
Step 6: Calculate the final value:
[tex]$$
75+10=85,
$$[/tex]
[tex]$$
85-1=84.
$$[/tex]
Thus, the value of [tex]$f(5)$[/tex] is [tex]$\boxed{84}$[/tex], which corresponds to option B.