Evaluate
12-8\sqrt{2}\approx 0.686291501
Factor
4 {(3 - 2 \sqrt{2})} = 0.686291501
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\left(2-2\sqrt{2}\right)^{2}
Multiply 2-2\sqrt{2} and 2-2\sqrt{2} to get \left(2-2\sqrt{2}\right)^{2}.
4-8\sqrt{2}+4\left(\sqrt{2}\right)^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(2-2\sqrt{2}\right)^{2}.
4-8\sqrt{2}+4\times 2
The square of \sqrt{2} is 2.
4-8\sqrt{2}+8
Multiply 4 and 2 to get 8.
12-8\sqrt{2}
Add 4 and 8 to get 12.
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Limits
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