Solve for x
x = -\frac{8}{7} = -1\frac{1}{7} \approx -1.142857143
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\left(x-1\right)\times 2+\left(x+2\right)\times 5=0
Variable x cannot be equal to any of the values -2,1 since division by zero is not defined. Multiply both sides of the equation by \left(x-1\right)\left(x+2\right), the least common multiple of x+2,x-1.
2x-2+\left(x+2\right)\times 5=0
Use the distributive property to multiply x-1 by 2.
2x-2+5x+10=0
Use the distributive property to multiply x+2 by 5.
7x-2+10=0
Combine 2x and 5x to get 7x.
7x+8=0
Add -2 and 10 to get 8.
7x=-8
Subtract 8 from both sides. Anything subtracted from zero gives its negation.
x=\frac{-8}{7}
Divide both sides by 7.
x=-\frac{8}{7}
Fraction \frac{-8}{7} can be rewritten as -\frac{8}{7} by extracting the negative sign.
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\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
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Limits
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