Evaluate
-\left(7x-1\right)\left(x+1\right)
Factor
-\left(7x-1\right)\left(x+1\right)
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-7x^{2}-6x+3-2
Combine -2x and -4x to get -6x.
-7x^{2}-6x+1
Subtract 2 from 3 to get 1.
-7x^{2}-6x+1
Multiply and combine like terms.
a+b=-6 ab=-7=-7
Factor the expression by grouping. First, the expression needs to be rewritten as -7x^{2}+ax+bx+1. To find a and b, set up a system to be solved.
a=1 b=-7
Since ab is negative, a and b have the opposite signs. Since a+b is negative, the negative number has greater absolute value than the positive. The only such pair is the system solution.
\left(-7x^{2}+x\right)+\left(-7x+1\right)
Rewrite -7x^{2}-6x+1 as \left(-7x^{2}+x\right)+\left(-7x+1\right).
-x\left(7x-1\right)-\left(7x-1\right)
Factor out -x in the first and -1 in the second group.
\left(7x-1\right)\left(-x-1\right)
Factor out common term 7x-1 by using distributive property.
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Simultaneous equation
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Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
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Limits
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