Solve for x (complex solution)
x\in \mathrm{C}
Solve for x
x\in \mathrm{R}
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x^{2}-9=x^{2}-9
Consider \left(x+3\right)\left(x-3\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 3.
x^{2}-9-x^{2}=-9
Subtract x^{2} from both sides.
-9=-9
Combine x^{2} and -x^{2} to get 0.
\text{true}
Compare -9 and -9.
x\in \mathrm{C}
This is true for any x.
x^{2}-9=x^{2}-9
Consider \left(x+3\right)\left(x-3\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 3.
x^{2}-9-x^{2}=-9
Subtract x^{2} from both sides.
-9=-9
Combine x^{2} and -x^{2} to get 0.
\text{true}
Compare -9 and -9.
x\in \mathrm{R}
This is true for any x.
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y = 3x + 4
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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
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