Evaluate
3-2\sqrt{2}\approx 0.171572875
Factor
3-2\sqrt{2}
Share
Copied to clipboard
\frac{\left(\sqrt{2}-1\right)\left(\sqrt{2}-1\right)}{\left(\sqrt{2}\right)^{2}-1^{2}}
Consider \left(\sqrt{2}+1\right)\left(\sqrt{2}-1\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}.
\frac{\left(\sqrt{2}-1\right)\left(\sqrt{2}-1\right)}{2-1}
Square \sqrt{2}. Square 1.
\frac{\left(\sqrt{2}-1\right)\left(\sqrt{2}-1\right)}{1}
Subtract 1 from 2 to get 1.
\left(\sqrt{2}-1\right)\left(\sqrt{2}-1\right)
Anything divided by one gives itself.
\left(\sqrt{2}-1\right)^{2}
Multiply \sqrt{2}-1 and \sqrt{2}-1 to get \left(\sqrt{2}-1\right)^{2}.
\left(\sqrt{2}\right)^{2}-2\sqrt{2}+1
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(\sqrt{2}-1\right)^{2}.
2-2\sqrt{2}+1
The square of \sqrt{2} is 2.
3-2\sqrt{2}
Add 2 and 1 to get 3.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}