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If y(x) = -2x^2 + 3 and v(x) = -√x, what is the range of (V°v)(x)?

a) (3.00)

b) (-0,3)

c) (-[infinity],0)

d) (-[infinity],00)

User Ceckenrode
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1 Answer

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Final Answer:

The range is (-∞, 0).

The correct option is c) (-∞, 0)

Step-by-step explanation:

The composition of functions
\(V \circ v\)is found by taking the function
V(x)\) and replacing \(x\) with \(v(x)\). Mathematically, this is expressed as
\((V \circ v)(x) = V(v(x))\).

Given
\(V(x) = -√(x)\), substituting \(v(x) = -2x^2 + 3\) into \(V(x)\) gives \((V \circ v)(x) = -√(-2x^2 + 3)\).

To determine the range of
\((V \circ v)(x)\), we need to analyze the behavior of the inner function
\(-2x^2 + 3\) under the square root. The expression
\(-2x^2 + 3\)represents a downward-facing parabola, and the square root of this expression is defined for values where
\(-2x^2 + 3 \geq 0\).

Solving
\(-2x^2 + 3 \geq 0\) gives \(x^2 \leq (3)/(2)\), which implies \(-\sqrt{(3)/(2)} \leq x \leq \sqrt{(3)/(2)}\).

However, since we are looking for the range of
\((V \circ v)(x) = -√(-2x^2 + 3)\), the negative square root introduces an additional negation. Therefore, the range is
\((-∞, 0)\). This means that for any valid input
\(x\), \((V \circ v)(x)\)will produce a value less than or equal to zero.

The correct option is c) (-∞, 0)

User Rae
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