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Let f:RrarrR be defined by f(x)=x^(2)+1....

Let `f:RrarrR` be defined by `f(x)=x^(2)+1`.
Find the pre-image of (i) 17 (ii) - 3.

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To find the pre-image of the given values under the function \( f(x) = x^2 + 1 \), we will solve for \( x \) when \( f(x) \) is equal to the specified values. ### Step-by-Step Solution: 1. **Finding the pre-image of 17:** - We set \( f(x) = 17 \). - This gives us the equation: \[ x^2 + 1 = 17 \] - Subtract 1 from both sides: \[ x^2 = 17 - 1 \] \[ x^2 = 16 \] - Now, take the square root of both sides: \[ x = \pm \sqrt{16} \] - Therefore, we have: \[ x = \pm 4 \] - Thus, the pre-images of 17 are \( x = 4 \) and \( x = -4 \). 2. **Finding the pre-image of -3:** - We set \( f(x) = -3 \). - This gives us the equation: \[ x^2 + 1 = -3 \] - Subtract 1 from both sides: \[ x^2 = -3 - 1 \] \[ x^2 = -4 \] - Since the square of a real number cannot be negative, there are no real solutions for this equation. Therefore, there is no pre-image for -3. ### Summary of Results: - The pre-images of 17 are \( x = 4 \) and \( x = -4 \). - There is no pre-image for -3.
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