Evaluate
\left(3-a\right)\left(a-5\right)
Expand
-a^{2}+8a-15
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2a-6-\left(3-a\right)^{2}
Use the distributive property to multiply 2 by a-3.
2a-6-\left(9-6a+a^{2}\right)
Use binomial theorem \left(p-q\right)^{2}=p^{2}-2pq+q^{2} to expand \left(3-a\right)^{2}.
2a-6-9+6a-a^{2}
To find the opposite of 9-6a+a^{2}, find the opposite of each term.
2a-15+6a-a^{2}
Subtract 9 from -6 to get -15.
8a-15-a^{2}
Combine 2a and 6a to get 8a.
2a-6-\left(3-a\right)^{2}
Use the distributive property to multiply 2 by a-3.
2a-6-\left(9-6a+a^{2}\right)
Use binomial theorem \left(p-q\right)^{2}=p^{2}-2pq+q^{2} to expand \left(3-a\right)^{2}.
2a-6-9+6a-a^{2}
To find the opposite of 9-6a+a^{2}, find the opposite of each term.
2a-15+6a-a^{2}
Subtract 9 from -6 to get -15.
8a-15-a^{2}
Combine 2a and 6a to get 8a.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\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
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}