Evaluating the Expression (2x-1)(4x^2+2x+1)-7(x^3+1) at x = -1/2
This article will guide you through the process of evaluating the expression (2x-1)(4x^2+2x+1)-7(x^3+1) at x = -1/2.
Step 1: Substitute the value of x
First, substitute x = -1/2 into the expression:
(2(-1/2)-1)(4(-1/2)^2+2(-1/2)+1)-7((-1/2)^3+1)
Step 2: Simplify the expression
Now, simplify the expression by performing the necessary arithmetic operations.
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Simplify the terms inside the parentheses:
- 2(-1/2) = -1
- 4(-1/2)^2 = 1
- 2(-1/2) = -1
- (-1/2)^3 = -1/8
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Substitute the simplified values back into the expression:
- (-1-1)(1-1+1)-7(-1/8+1)
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Continue simplifying:
- (-2)(1)-7(7/8)
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Perform the multiplication:
- -2 - 49/8
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Find a common denominator:
- -16/8 - 49/8
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Combine the terms:
- -65/8
Conclusion
Therefore, the value of the expression (2x-1)(4x^2+2x+1)-7(x^3+1) at x = -1/2 is -65/8.