Precalculus Examples
3∑x=272x
Step 1
Step 1.1
Combine 72 and x.
7x2
Step 1.2
Rewrite the summation.
3∑x=27x2
3∑x=27x2
Step 2
Expand the series for each value of x.
7⋅22+7⋅32
Step 3
Step 3.1
Combine the numerators over the common denominator.
7⋅2+7⋅32
Step 3.2
Simplify each term.
Step 3.2.1
Multiply 7 by 2.
14+7⋅32
Step 3.2.2
Multiply 7 by 3.
14+212
14+212
Step 3.3
Add 14 and 21.
352
352
Step 4
The result can be shown in multiple forms.
Exact Form:
352
Decimal Form:
17.5
Mixed Number Form:
1712