40,857 views
39 votes
39 votes
Evaluate -b with exponent of 2 - 2bx with exponent of 2 on the x - x = -2

Evaluate -b with exponent of 2 - 2bx with exponent of 2 on the x - x = -2-example-1
User CPlusSharp
by
3.2k points

1 Answer

11 votes
11 votes

To solve the exercise, we replace x by -2 in the given expression:


\begin{gathered} -b^2-2bx^2-x \\ -b^2-2b(-2)^2-(-2) \end{gathered}

Now, we operate:


\begin{gathered} -b^2-2b(-2)^2-(-2)=-b^2-2b(-2)\cdot(-2)^{}-(-2) \\ -b^2-2b(-2)^2-(-2)=-b^2-2b\cdot4+2 \\ -b^2-2b\mleft(-2\mright)^2-\mleft(-2\mright)=-b^2-8b+2 \\ \text{ Because} \\ (-2)\cdot(-2)=2\cdot2=4 \\ \text{ and} \\ ^{}-(-2)=2 \end{gathered}

Therefore, the result of evaluate the given expression when x = -2 is:


$$\boldsymbol{-b}^{\boldsymbol{2}}\boldsymbol{-8b+2}$$

User Danialk
by
3.0k points