Evaluate
\frac{b}{8a}-\frac{1}{2}
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\frac{b}{8a}-\frac{1}{2}
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\frac{4a-7b}{8a}-\frac{8\left(a-b\right)}{8a}
Factor the expressions that are not already factored in \frac{8a-8b}{8a}.
\frac{4a-7b}{8a}-\frac{a-b}{a}
Cancel out 8 in both numerator and denominator.
\frac{4a-7b}{8a}-\frac{8\left(a-b\right)}{8a}
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of 8a and a is 8a. Multiply \frac{a-b}{a} times \frac{8}{8}.
\frac{4a-7b-8\left(a-b\right)}{8a}
Since \frac{4a-7b}{8a} and \frac{8\left(a-b\right)}{8a} have the same denominator, subtract them by subtracting their numerators.
\frac{4a-7b-8a+8b}{8a}
Do the multiplications in 4a-7b-8\left(a-b\right).
\frac{-4a+b}{8a}
Combine like terms in 4a-7b-8a+8b.
\frac{4a-7b}{8a}-\frac{8\left(a-b\right)}{8a}
Factor the expressions that are not already factored in \frac{8a-8b}{8a}.
\frac{4a-7b}{8a}-\frac{a-b}{a}
Cancel out 8 in both numerator and denominator.
\frac{4a-7b}{8a}-\frac{8\left(a-b\right)}{8a}
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of 8a and a is 8a. Multiply \frac{a-b}{a} times \frac{8}{8}.
\frac{4a-7b-8\left(a-b\right)}{8a}
Since \frac{4a-7b}{8a} and \frac{8\left(a-b\right)}{8a} have the same denominator, subtract them by subtracting their numerators.
\frac{4a-7b-8a+8b}{8a}
Do the multiplications in 4a-7b-8\left(a-b\right).
\frac{-4a+b}{8a}
Combine like terms in 4a-7b-8a+8b.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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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}