Let [tex]$f(x)=3 x^2-5 x$[/tex]. Evaluate each of the following:

a) [tex]f(2) = \quad[/tex]
b) [tex]f(-8) = \quad[/tex]
c) [tex]f(7) = \quad[/tex]
d) [tex]f(-1) = \quad[/tex]



Answer :

Absolutely! Let's go through the detailed step-by-step solutions for each requested value of the function [tex]\( f(x) = 3x^2 - 5x \)[/tex].

### Part a) [tex]\( f(2) \)[/tex]

For [tex]\( x = 2 \)[/tex]:
[tex]\[ f(2) = 3(2)^2 - 5(2) \][/tex]
This evaluates to:
[tex]\[ f(2) = 3 \cdot 4 - 5 \cdot 2 = 12 - 10 = 2 \][/tex]
Thus:
[tex]\[ f(2) = 2 \][/tex]

### Part b) [tex]\( f(-8) \)[/tex]

For [tex]\( x = -8 \)[/tex]:
[tex]\[ f(-8) = 3(-8)^2 - 5(-8) \][/tex]
This evaluates to:
[tex]\[ f(-8) = 3 \cdot 64 - 5 \cdot (-8) = 192 + 40 = 232 \][/tex]
Thus:
[tex]\[ f(-8) = 232 \][/tex]

### Part c) [tex]\( f(7) \)[/tex]

For [tex]\( x = 7 \)[/tex]:
[tex]\[ f(7) = 3(7)^2 - 5(7) \][/tex]
This evaluates to:
[tex]\[ f(7) = 3 \cdot 49 - 5 \cdot 7 = 147 - 35 = 112 \][/tex]
Thus:
[tex]\[ f(7) = 112 \][/tex]

### Part d) [tex]\( f(-1) \)[/tex]

For [tex]\( x = -1 \)[/tex]:
[tex]\[ f(-1) = 3(-1)^2 - 5(-1) \][/tex]
This evaluates to:
[tex]\[ f(-1) = 3 \cdot 1 - 5 \cdot (-1) = 3 + 5 = 8 \][/tex]
Thus:
[tex]\[ f(-1) = 8 \][/tex]

In summary:
[tex]\[ f(2) = 2, \quad f(-8) = 232, \quad f(7) = 112, \quad f(-1) = 8 \][/tex]