Evaluate
\left(3k-1\right)^{2}
Expand
9k^{2}-6k+1
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9k^{2}+6k+1-4k\times 3
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(3k+1\right)^{2}.
9k^{2}+6k+1-12k
Multiply 4 and 3 to get 12.
9k^{2}-6k+1
Combine 6k and -12k to get -6k.
9k^{2}+6k+1-4k\times 3
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(3k+1\right)^{2}.
9k^{2}+6k+1-12k
Multiply 4 and 3 to get 12.
9k^{2}-6k+1
Combine 6k and -12k to get -6k.
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