Calculus Examples
f(x)=x2+3x
Step 1
Consider the difference quotient formula.
f(x+h)-f(x)h
Step 2
Step 2.1
Evaluate the function at x=x+h.
Step 2.1.1
Replace the variable x with x+h in the expression.
f(x+h)=(x+h)2+3(x+h)
Step 2.1.2
Simplify the result.
Step 2.1.2.1
Simplify each term.
Step 2.1.2.1.1
Rewrite (x+h)2 as (x+h)(x+h).
f(x+h)=(x+h)(x+h)+3(x+h)
Step 2.1.2.1.2
Expand (x+h)(x+h) using the FOIL Method.
Step 2.1.2.1.2.1
Apply the distributive property.
f(x+h)=x(x+h)+h(x+h)+3(x+h)
Step 2.1.2.1.2.2
Apply the distributive property.
f(x+h)=x⋅x+xh+h(x+h)+3(x+h)
Step 2.1.2.1.2.3
Apply the distributive property.
f(x+h)=x⋅x+xh+hx+h⋅h+3(x+h)
f(x+h)=x⋅x+xh+hx+h⋅h+3(x+h)
Step 2.1.2.1.3
Simplify and combine like terms.
Step 2.1.2.1.3.1
Simplify each term.
Step 2.1.2.1.3.1.1
Multiply x by x.
f(x+h)=x2+xh+hx+h⋅h+3(x+h)
Step 2.1.2.1.3.1.2
Multiply h by h.
f(x+h)=x2+xh+hx+h2+3(x+h)
f(x+h)=x2+xh+hx+h2+3(x+h)
Step 2.1.2.1.3.2
Add xh and hx.
Step 2.1.2.1.3.2.1
Reorder x and h.
f(x+h)=x2+hx+hx+h2+3(x+h)
Step 2.1.2.1.3.2.2
Add hx and hx.
f(x+h)=x2+2hx+h2+3(x+h)
f(x+h)=x2+2hx+h2+3(x+h)
f(x+h)=x2+2hx+h2+3(x+h)
Step 2.1.2.1.4
Apply the distributive property.
f(x+h)=x2+2hx+h2+3x+3h
f(x+h)=x2+2hx+h2+3x+3h
Step 2.1.2.2
The final answer is x2+2hx+h2+3x+3h.
x2+2hx+h2+3x+3h
x2+2hx+h2+3x+3h
x2+2hx+h2+3x+3h
Step 2.2
Reorder.
Step 2.2.1
Move 3x.
x2+2hx+h2+3h+3x
Step 2.2.2
Move x2.
2hx+h2+x2+3h+3x
Step 2.2.3
Reorder 2hx and h2.
h2+2hx+x2+3h+3x
h2+2hx+x2+3h+3x
Step 2.3
Find the components of the definition.
f(x+h)=h2+2hx+x2+3h+3x
f(x)=x2+3x
f(x+h)=h2+2hx+x2+3h+3x
f(x)=x2+3x
Step 3
Plug in the components.
f(x+h)-f(x)h=h2+2hx+x2+3h+3x-(x2+3x)h
Step 4
Step 4.1
Simplify the numerator.
Step 4.1.1
Apply the distributive property.
h2+2hx+x2+3h+3x-x2-(3x)h
Step 4.1.2
Multiply 3 by -1.
h2+2hx+x2+3h+3x-x2-3xh
Step 4.1.3
Subtract x2 from x2.
h2+2hx+3h+3x+0-3xh
Step 4.1.4
Add h2 and 0.
h2+2hx+3h+3x-3xh
Step 4.1.5
Subtract 3x from 3x.
h2+2hx+3h+0h
Step 4.1.6
Add h2+2hx+3h and 0.
h2+2hx+3hh
Step 4.1.7
Factor h out of h2+2hx+3h.
Step 4.1.7.1
Factor h out of h2.
h⋅h+2hx+3hh
Step 4.1.7.2
Factor h out of 2hx.
h(h)+h(2x)+3hh
Step 4.1.7.3
Factor h out of 3h.
h(h)+h(2x)+h⋅3h
Step 4.1.7.4
Factor h out of h(h)+h(2x).
h(h+2x)+h⋅3h
Step 4.1.7.5
Factor h out of h(h+2x)+h⋅3.
h(h+2x+3)h
h(h+2x+3)h
h(h+2x+3)h
Step 4.2
Reduce the expression by cancelling the common factors.
Step 4.2.1
Cancel the common factor of h.
Step 4.2.1.1
Cancel the common factor.
h(h+2x+3)h
Step 4.2.1.2
Divide h+2x+3 by 1.
h+2x+3
h+2x+3
Step 4.2.2
Reorder h and 2x.
2x+h+3
2x+h+3
2x+h+3
Step 5