College

Given: [tex]f(x) = 3x^2 + 2x - 1[/tex]

What is the value of [tex]f(5)[/tex]?

A. 39
B. 84
C. 234
D. 624

Answer :

Let's find the value of [tex]\( f(5) \)[/tex] for the given function [tex]\( f(x) = 3x^2 + 2x - 1 \)[/tex].

1. Start by substituting [tex]\( x \)[/tex] with 5 in the function:
[tex]\[ f(x) = 3x^2 + 2x - 1 \][/tex]

2. Plug [tex]\( x = 5 \)[/tex] into the function:
[tex]\[ f(5) = 3(5)^2 + 2(5) - 1 \][/tex]

3. Calculate [tex]\( (5)^2 \)[/tex]:
[tex]\[ 5^2 = 25 \][/tex]

4. Multiply 25 by 3:
[tex]\[ 3 \cdot 25 = 75 \][/tex]

5. Multiply 2 by 5:
[tex]\[ 2 \cdot 5 = 10 \][/tex]

6. Add these results together:
[tex]\[ 75 + 10 = 85 \][/tex]

7. Finally, subtract 1:
[tex]\[ 85 - 1 = 84 \][/tex]

So, the value of [tex]\( f(5) \)[/tex] is [tex]\( 84 \)[/tex].

Therefore, the correct answer is:
[tex]\[ \boxed{84} \][/tex]