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42x-21
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42x-21
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9x^{2}+12x+4-\left(3x-5\right)^{2}
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(3x+2\right)^{2}.
9x^{2}+12x+4-\left(9x^{2}-30x+25\right)
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(3x-5\right)^{2}.
9x^{2}+12x+4-9x^{2}+30x-25
To find the opposite of 9x^{2}-30x+25, find the opposite of each term.
12x+4+30x-25
Combine 9x^{2} and -9x^{2} to get 0.
42x+4-25
Combine 12x and 30x to get 42x.
42x-21
Subtract 25 from 4 to get -21.
9x^{2}+12x+4-\left(3x-5\right)^{2}
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(3x+2\right)^{2}.
9x^{2}+12x+4-\left(9x^{2}-30x+25\right)
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(3x-5\right)^{2}.
9x^{2}+12x+4-9x^{2}+30x-25
To find the opposite of 9x^{2}-30x+25, find the opposite of each term.
12x+4+30x-25
Combine 9x^{2} and -9x^{2} to get 0.
42x+4-25
Combine 12x and 30x to get 42x.
42x-21
Subtract 25 from 4 to get -21.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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y = 3x + 4
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Matrix
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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}