Evaluate
\left(3-x\right)\left(x+4\right)
Expand
12-x-x^{2}
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x^{2}+8x+16-\left(x+4\right)\left(2x+1\right)
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+4\right)^{2}.
x^{2}+8x+16-\left(2x^{2}+9x+4\right)
Use the distributive property to multiply x+4 by 2x+1 and combine like terms.
x^{2}+8x+16-2x^{2}-9x-4
To find the opposite of 2x^{2}+9x+4, find the opposite of each term.
-x^{2}+8x+16-9x-4
Combine x^{2} and -2x^{2} to get -x^{2}.
-x^{2}-x+16-4
Combine 8x and -9x to get -x.
-x^{2}-x+12
Subtract 4 from 16 to get 12.
x^{2}+8x+16-\left(x+4\right)\left(2x+1\right)
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+4\right)^{2}.
x^{2}+8x+16-\left(2x^{2}+9x+4\right)
Use the distributive property to multiply x+4 by 2x+1 and combine like terms.
x^{2}+8x+16-2x^{2}-9x-4
To find the opposite of 2x^{2}+9x+4, find the opposite of each term.
-x^{2}+8x+16-9x-4
Combine x^{2} and -2x^{2} to get -x^{2}.
-x^{2}-x+16-4
Combine 8x and -9x to get -x.
-x^{2}-x+12
Subtract 4 from 16 to get 12.
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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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