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Evaluate x^(2)+4x+7 when x=-2+sqrt(-3)....

Evaluate `x^(2)+4x+7` when `x=-2+sqrt(-3)`.

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To evaluate the expression \( x^2 + 4x + 7 \) when \( x = -2 + \sqrt{-3} \), we will follow these steps: ### Step 1: Substitute the value of \( x \) We start by substituting \( x = -2 + \sqrt{-3} \) into the expression: \[ x^2 + 4x + 7 = (-2 + \sqrt{-3})^2 + 4(-2 + \sqrt{-3}) + 7 \] ### Step 2: Calculate \( x^2 \) Now, we calculate \( (-2 + \sqrt{-3})^2 \): \[ (-2 + \sqrt{-3})^2 = (-2)^2 + 2(-2)(\sqrt{-3}) + (\sqrt{-3})^2 \] \[ = 4 - 4\sqrt{-3} + (-3) = 4 - 4\sqrt{-3} - 3 = 1 - 4\sqrt{-3} \] ### Step 3: Calculate \( 4x \) Next, we calculate \( 4(-2 + \sqrt{-3}) \): \[ 4(-2 + \sqrt{-3}) = 4(-2) + 4(\sqrt{-3}) = -8 + 4\sqrt{-3} \] ### Step 4: Combine all parts Now we can combine all parts: \[ x^2 + 4x + 7 = (1 - 4\sqrt{-3}) + (-8 + 4\sqrt{-3}) + 7 \] Combining the constant terms: \[ 1 - 8 + 7 = 0 \] And combining the terms with \( \sqrt{-3} \): \[ -4\sqrt{-3} + 4\sqrt{-3} = 0 \] ### Step 5: Final result Thus, we have: \[ x^2 + 4x + 7 = 0 + 0 = 0 \] So, the final answer is: \[ \boxed{0} \]
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