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-2a^{2}-3a-21
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-2a^{2}-3a-21
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-9a-18-\left(2a^{2}-a+3\right)+5a
Use the distributive property to multiply -9 by a+2.
-9a-18-2a^{2}+a-3+5a
To find the opposite of 2a^{2}-a+3, find the opposite of each term.
-8a-18-2a^{2}-3+5a
Combine -9a and a to get -8a.
-8a-21-2a^{2}+5a
Subtract 3 from -18 to get -21.
-3a-21-2a^{2}
Combine -8a and 5a to get -3a.
-9a-18-\left(2a^{2}-a+3\right)+5a
Use the distributive property to multiply -9 by a+2.
-9a-18-2a^{2}+a-3+5a
To find the opposite of 2a^{2}-a+3, find the opposite of each term.
-8a-18-2a^{2}-3+5a
Combine -9a and a to get -8a.
-8a-21-2a^{2}+5a
Subtract 3 from -18 to get -21.
-3a-21-2a^{2}
Combine -8a and 5a to get -3a.
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\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
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Limits
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