Evaluate
9-2\sqrt{14}\approx 1.516685226
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9-2\sqrt{14}
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\left(\sqrt{7}\right)^{2}-2\sqrt{7}\sqrt{2}+\left(\sqrt{2}\right)^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(\sqrt{7}-\sqrt{2}\right)^{2}.
7-2\sqrt{7}\sqrt{2}+\left(\sqrt{2}\right)^{2}
The square of \sqrt{7} is 7.
7-2\sqrt{14}+\left(\sqrt{2}\right)^{2}
To multiply \sqrt{7} and \sqrt{2}, multiply the numbers under the square root.
7-2\sqrt{14}+2
The square of \sqrt{2} is 2.
9-2\sqrt{14}
Add 7 and 2 to get 9.
\left(\sqrt{7}\right)^{2}-2\sqrt{7}\sqrt{2}+\left(\sqrt{2}\right)^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(\sqrt{7}-\sqrt{2}\right)^{2}.
7-2\sqrt{7}\sqrt{2}+\left(\sqrt{2}\right)^{2}
The square of \sqrt{7} is 7.
7-2\sqrt{14}+\left(\sqrt{2}\right)^{2}
To multiply \sqrt{7} and \sqrt{2}, multiply the numbers under the square root.
7-2\sqrt{14}+2
The square of \sqrt{2} is 2.
9-2\sqrt{14}
Add 7 and 2 to get 9.
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Limits
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