Evaluate
-390x+\frac{21}{x}
Factor
\frac{3\left(7-130x^{2}\right)}{x}
Graph
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\frac{-390xx}{x}+\frac{21}{x}
To add or subtract expressions, expand them to make their denominators the same. Multiply -390x times \frac{x}{x}.
\frac{-390xx+21}{x}
Since \frac{-390xx}{x} and \frac{21}{x} have the same denominator, add them by adding their numerators.
\frac{-390x^{2}+21}{x}
Do the multiplications in -390xx+21.
Examples
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Matrix
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Simultaneous equation
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Integration
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Limits
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