Evaluate
9\left(7k-3\right)\left(k+1\right)
Expand
63k^{2}+36k-27
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7\left(9k^{2}-6k+1\right)+26\left(3k-1\right)-8
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(3k-1\right)^{2}.
63k^{2}-42k+7+26\left(3k-1\right)-8
Use the distributive property to multiply 7 by 9k^{2}-6k+1.
63k^{2}-42k+7+78k-26-8
Use the distributive property to multiply 26 by 3k-1.
63k^{2}+36k+7-26-8
Combine -42k and 78k to get 36k.
63k^{2}+36k-19-8
Subtract 26 from 7 to get -19.
63k^{2}+36k-27
Subtract 8 from -19 to get -27.
7\left(9k^{2}-6k+1\right)+26\left(3k-1\right)-8
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(3k-1\right)^{2}.
63k^{2}-42k+7+26\left(3k-1\right)-8
Use the distributive property to multiply 7 by 9k^{2}-6k+1.
63k^{2}-42k+7+78k-26-8
Use the distributive property to multiply 26 by 3k-1.
63k^{2}+36k+7-26-8
Combine -42k and 78k to get 36k.
63k^{2}+36k-19-8
Subtract 26 from 7 to get -19.
63k^{2}+36k-27
Subtract 8 from -19 to get -27.
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Limits
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