Examples
f(x)=4x-4f(x)=4x−4 , x=2x=2
Step 1
Consider the difference quotient formula.
f(x+h)-f(x)hf(x+h)−f(x)h
Step 2
Step 2.1
Evaluate the function at x=x+hx=x+h.
Step 2.1.1
Replace the variable xx with x+hx+h in the expression.
f(x+h)=4(x+h)-4f(x+h)=4(x+h)−4
Step 2.1.2
Simplify the result.
Step 2.1.2.1
Apply the distributive property.
f(x+h)=4x+4h-4f(x+h)=4x+4h−4
Step 2.1.2.2
The final answer is 4x+4h-44x+4h−4.
4x+4h-44x+4h−4
4x+4h-44x+4h−4
4x+4h-44x+4h−4
Step 2.2
Reorder 4x4x and 4h4h.
4h+4x-44h+4x−4
Step 2.3
Find the components of the definition.
f(x+h)=4h+4x-4f(x+h)=4h+4x−4
f(x)=4x-4f(x)=4x−4
f(x+h)=4h+4x-4f(x+h)=4h+4x−4
f(x)=4x-4f(x)=4x−4
Step 3
Plug in the components.
f(x+h)-f(x)h=4h+4x-4-(4x-4)hf(x+h)−f(x)h=4h+4x−4−(4x−4)h
Step 4
Step 4.1
Simplify the numerator.
Step 4.1.1
Factor 44 out of 4x-44x−4.
Step 4.1.1.1
Factor 44 out of 4x4x.
4h+4x-4-(4(x)-4)h4h+4x−4−(4(x)−4)h
Step 4.1.1.2
Factor 44 out of -4−4.
4h+4x-4-(4(x)+4(-1))h4h+4x−4−(4(x)+4(−1))h
Step 4.1.1.3
Factor 44 out of 4(x)+4(-1)4(x)+4(−1).
4h+4x-4-(4(x-1))h4h+4x−4−(4(x−1))h
4h+4x-4-1⋅4(x-1)h4h+4x−4−1⋅4(x−1)h
Step 4.1.2
Multiply -1−1 by 44.
4h+4x-4-4(x-1)h4h+4x−4−4(x−1)h
Step 4.1.3
Factor 44 out of 4h+4x-4-4(x-1)4h+4x−4−4(x−1).
Step 4.1.3.1
Factor 44 out of 4h4h.
4h+4x-4-4(x-1)h4h+4x−4−4(x−1)h
Step 4.1.3.2
Factor 44 out of 4x4x.
4h+4(x)-4-4(x-1)h4h+4(x)−4−4(x−1)h
Step 4.1.3.3
Factor 44 out of -4−4.
4h+4(x)+4(-1)-4(x-1)h4h+4(x)+4(−1)−4(x−1)h
Step 4.1.3.4
Factor 44 out of -4(x-1)−4(x−1).
4h+4(x)+4(-1)+4(-(x-1))h4h+4(x)+4(−1)+4(−(x−1))h
Step 4.1.3.5
Factor 44 out of 4h+4(x)4h+4(x).
4(h+x)+4(-1)+4(-(x-1))h4(h+x)+4(−1)+4(−(x−1))h
Step 4.1.3.6
Factor 44 out of 4(h+x)+4(-1)4(h+x)+4(−1).
4(h+x-1)+4(-(x-1))h4(h+x−1)+4(−(x−1))h
Step 4.1.3.7
Factor 44 out of 4(h+x-1)+4(-(x-1))4(h+x−1)+4(−(x−1)).
4(h+x-1-(x-1))h4(h+x−1−(x−1))h
4(h+x-1-(x-1))h4(h+x−1−(x−1))h
Step 4.1.4
Apply the distributive property.
4(h+x-1-x--1)h4(h+x−1−x−−1)h
Step 4.1.5
Multiply -1−1 by -1.
4(h+x-1-x+1)h
Step 4.1.6
Subtract x from x.
4(h+0-1+1)h
Step 4.1.7
Add h and 0.
4(h-1+1)h
Step 4.1.8
Add -1 and 1.
4(h+0)h
Step 4.1.9
Add h and 0.
4hh
4hh
Step 4.2
Cancel the common factor of h.
Step 4.2.1
Cancel the common factor.
4hh
Step 4.2.2
Divide 4 by 1.
4
4
4
Step 5