Evaluate
-\frac{15}{7}\approx -2.142857143
Factor
-\frac{15}{7} = -2\frac{1}{7} = -2.142857142857143
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\frac{6}{7}-\frac{21}{7}
Convert 3 to fraction \frac{21}{7}.
\frac{6-21}{7}
Since \frac{6}{7} and \frac{21}{7} have the same denominator, subtract them by subtracting their numerators.
-\frac{15}{7}
Subtract 21 from 6 to get -15.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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y = 3x + 4
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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
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