Use the definition of the derivative to find [tex]f^{\prime}(x)[/tex].

[tex]\[ f(x) = \frac{3}{2} x^2 + 4x - 5 \][/tex]

Step 1 of 2: Find and simplify the difference quotient. Use [tex]h[/tex] for the change in the independent variable.



Answer :

To find the derivative [tex]\( f^{\prime}(x) \)[/tex] of the function [tex]\( f(x) = \frac{3}{2}x^2 + 4x - 5 \)[/tex], we start with the definition of the derivative:

[tex]\[ f^{\prime}(x) = \lim_{h \to 0} \frac{f(x + h) - f(x)}{h} \][/tex]

First, let's find [tex]\( f(x + h) \)[/tex]:

[tex]\[ f(x + h) = \frac{3}{2}(x + h)^2 + 4(x + h) - 5 \][/tex]

We need to expand and simplify [tex]\( f(x + h) \)[/tex]. Start by expanding [tex]\( (x + h)^2 \)[/tex]:

[tex]\[ (x + h)^2 = x^2 + 2xh + h^2 \][/tex]

Substitute back into the expression for [tex]\( f(x + h) \)[/tex]:

[tex]\[ f(x + h) = \frac{3}{2}(x^2 + 2xh + h^2) + 4(x + h) - 5 \][/tex]

Now distribute:

[tex]\[ f(x + h) = \frac{3}{2}x^2 + \frac{3}{2}(2xh) + \frac{3}{2}h^2 + 4x + 4h - 5 \][/tex]

Simplify further:

[tex]\[ f(x + h) = \frac{3}{2}x^2 + 3xh + \frac{3}{2}h^2 + 4x + 4h - 5 \][/tex]

Next, compute the difference [tex]\( f(x + h) - f(x) \)[/tex]:

[tex]\[ f(x + h) - f(x) = \left( \frac{3}{2}x^2 + 3xh + \frac{3}{2}h^2 + 4x + 4h - 5 \right) - \left( \frac{3}{2}x^2 + 4x - 5 \right) \][/tex]

Distribute and combine like terms:

[tex]\[ f(x + h) - f(x) = \frac{3}{2}x^2 + 3xh + \frac{3}{2}h^2 + 4x + 4h - 5 - \frac{3}{2}x^2 - 4x + 5 \][/tex]

[tex]\[ f(x + h) - f(x) = 3xh + \frac{3}{2}h^2 + 4h \][/tex]

Finally, divide by [tex]\( h \)[/tex] to obtain the difference quotient:

[tex]\[ \frac{f(x + h) - f(x)}{h} = \frac{3xh + \frac{3}{2}h^2 + 4h}{h} \][/tex]

[tex]\[ \frac{f(x + h) - f(x)}{h} = \frac{h(3x + \frac{3}{2}h + 4)}{h} \][/tex]

Simplify by canceling [tex]\( h \)[/tex]:

[tex]\[ \frac{f(x + h) - f(x)}{h} = 3x + \frac{3}{2}h + 4 \][/tex]

This is the simplified form of the difference quotient.

In the next step, we will take the limit as [tex]\( h \)[/tex] approaches 0.