Evaluate
\left(a+2b\right)^{2}-4c^{2}
Expand
a^{2}+4ab+4b^{2}-4c^{2}
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a^{2}+4ab+4b^{2}-\left(2c\right)^{2}
Use binomial theorem \left(p+q\right)^{2}=p^{2}+2pq+q^{2} to expand \left(a+2b\right)^{2}.
a^{2}+4ab+4b^{2}-2^{2}c^{2}
Expand \left(2c\right)^{2}.
a^{2}+4ab+4b^{2}-4c^{2}
Calculate 2 to the power of 2 and get 4.
a^{2}+4ab+4b^{2}-\left(2c\right)^{2}
Use binomial theorem \left(p+q\right)^{2}=p^{2}+2pq+q^{2} to expand \left(a+2b\right)^{2}.
a^{2}+4ab+4b^{2}-2^{2}c^{2}
Expand \left(2c\right)^{2}.
a^{2}+4ab+4b^{2}-4c^{2}
Calculate 2 to the power of 2 and get 4.
Examples
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Simultaneous equation
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Integration
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Limits
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