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Precalculus Examples
4∑k=12k
Step 1
Expand the series for each value of k.
2⋅1+2⋅2+2⋅3+2⋅4
Step 2
Step 2.1
Multiply 2 by 1.
2+2⋅2+2⋅3+2⋅4
Step 2.2
Multiply 2 by 2.
2+4+2⋅3+2⋅4
Step 2.3
Add 2 and 4.
6+2⋅3+2⋅4
Step 2.4
Multiply 2 by 3.
6+6+2⋅4
Step 2.5
Add 6 and 6.
12+2⋅4
Step 2.6
Multiply 2 by 4.
12+8
Step 2.7
Add 12 and 8.
20
20