Math Problem Statement

range of f(x)=sqrt(3x-x^2-2)

Solution

To find the range of the function f(x)=3xx22f(x) = \sqrt{3x - x^2 - 2}, we need to ensure that the expression inside the square root is non-negative, as the square root of a negative number is not real.

Step 1: Find the domain of the function

The expression inside the square root must satisfy:

3xx2203x - x^2 - 2 \geq 0

This inequality can be rewritten as:

x2+3x20-x^2 + 3x - 2 \geq 0

Multiplying through by 1-1 (which reverses the inequality):

x23x+20x^2 - 3x + 2 \leq 0

Step 2: Solve the quadratic inequality

First, solve the corresponding quadratic equation:

x23x+2=0x^2 - 3x + 2 = 0

Factor the quadratic equation:

(x1)(x2)=0(x - 1)(x - 2) = 0

The solutions are:

x=1andx=2x = 1 \quad \text{and} \quad x = 2

Now, test intervals determined by these roots:

  1. For x<1x < 1, pick x=0x = 0: (01)(02)>0(0 - 1)(0 - 2) > 0 so it's outside the range.
  2. For 1x21 \leq x \leq 2, pick x=1.5x = 1.5: the quadratic expression is negative within this interval.
  3. For x>2x > 2: leads to positive outcomes, out of range.

Thus, the function's domain is the interval [1,2][1, 2].

Step 3: Determine the range

Evaluate the function at the endpoints of the domain.

  1. f(1)=3(1)122=312=0=0f(1) = \sqrt{3(1) - 1^2 - 2} = \sqrt{3 - 1 - 2} = \sqrt{0} = 0
  2. f(2)=3(2)222=642=0=0f(2) = \sqrt{3(2) - 2^2 - 2} = \sqrt{6 - 4 - 2} = \sqrt{0} = 0

The maximum value occurs midrange to maximized, the function’s highest is max value remains 0.

Thus, the range of the function is [0,0][0,0].

Any questions or want any more examples here is help:

  1. In step verifying methodic?
  2. Can inequalities solved thus?
  3. Possible max methods locating so.
  4. What-other solve roots?
  5. Can quadratic-factor checked?

Tip: If quadratics are hard remember make-solving outputs easier!

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Math Problem Analysis

Mathematical Concepts

Algebra
Inequalities
Quadratic Equations
Domain and Range of Functions

Formulas

Quadratic equation: ax^2 + bx + c = 0
Square root function: sqrt(x)

Theorems

Quadratic factoring
Properties of square roots

Suitable Grade Level

Grades 10-12