We read your photo as:

Given functions: f(x) = 2x + 3 where x [-1, 2) and g(x) = x2. Determine g(sqrt(3)), f⁻¹(x), a if g(a+2) − f(a+2) = 0, and the domain of f⁻¹(x).

Mathematics

ScanSolve AI Answer

Step-by-step solution

15 steps

Here are the solutions to the problems:

Given functions:
f(x)=2x+3f(x) = 2x + 3 where x∈[−1,2)x \in [-1, 2)
g(x)=x2g(x) = x^2 with domain x∈Rx \in \mathbb{R}

2.3.1 Determine the value of g(3)g(\sqrt{3}).

  1. Substitute 3\sqrt{3} into the function g(x)g(x).

    g(x)=x2g(x) = x^2 g(3)=(3)2g(\sqrt{3}) = (\sqrt{3})^2
  2. Simplify the expression.

    g(3)=3g(\sqrt{3}) = 3

    The value of g(3)g(\sqrt{3}) is 3\boxed{3}.

    2.3.2 Determine the equation of f−1(x)f^{-1}(x) in the form y=...y=....

  3. Replace f(x)f(x) with yy.

    y=2x+3y = 2x + 3
  4. Swap xx and yy to find the inverse.

    x=2y+3x = 2y + 3
  5. Solve for yy.

    x−3=2yx - 3 = 2y y=x−32y = \frac{x - 3}{2}

    The equation of f−1(x)f^{-1}(x) is y=x−32\boxed{y = \frac{x - 3}{2}}.

    2.3.3 Determine the value of aa if g(a+2)−f(a+2)=0g(a+2) - f(a+2) = 0.

  6. Substitute (a+2)(a+2) into g(x)g(x) and f(x)f(x).

    g(a+2)=(a+2)2g(a+2) = (a+2)^2 f(a+2)=2(a+2)+3f(a+2) = 2(a+2) + 3
  7. Set up the equation g(a+2)−f(a+2)=0g(a+2) - f(a+2) = 0.

    (a+2)2−(2(a+2)+3)=0(a+2)^2 - (2(a+2) + 3) = 0
  8. Expand and simplify the equation.

    (a2+4a+4)−(2a+4+3)=0(a^2 + 4a + 4) - (2a + 4 + 3) = 0 a2+4a+4−2a−7=0a^2 + 4a + 4 - 2a - 7 = 0 a2+2a−3=0a^2 + 2a - 3 = 0
  9. Factor the quadratic equation.

    (a+3)(a−1)=0(a+3)(a-1) = 0
  10. Solve for aa.

    a+3=0  ⟹  a=−3a+3 = 0 \implies a = -3 a−1=0  ⟹  a=1a-1 = 0 \implies a = 1

    The values of aa are −3 or 1\boxed{-3 \text{ or } 1}.

    2.3.4 Write down the domain for f−1(x)f^{-1}(x).

  11. Determine the range of f(x)f(x).

    The domain of f−1(x)f^{-1}(x) is the range of f(x)f(x).
    The domain of f(x)f(x) is x∈[−1,2)x \in [-1, 2).
    For f(x)=2x+3f(x) = 2x+3:
    When x=−1x = -1, f(−1)=2(−1)+3=−2+3=1f(-1) = 2(-1) + 3 = -2 + 3 = 1.
    When x=2x = 2, f(2)=2(2)+3=4+3=7f(2) = 2(2) + 3 = 4 + 3 = 7.
    Since f(x)f(x) is a linear function with a positive slope, its range is [1,7)[1, 7).

  12. State the domain of f−1(x)f^{-1}(x).

    The domain for f−1(x)f^{-1}(x) is x∈[1,7)\boxed{x \in [1, 7)}.

    2.3.5 Prove that f(f−1(x))=f−1(f(x))f(f^{-1}(x)) = f^{-1}(f(x)).

  13. Calculate f(f−1(x))f(f^{-1}(x)).

    We have f(x)=2x+3f(x) = 2x+3 and f−1(x)=x−32f^{-1}(x) = \frac{x-3}{2}.

    f(f−1(x))=f(x−32)f(f^{-1}(x)) = f\left(\frac{x-3}{2}\right) f(f−1(x))=2(x−32)+3f(f^{-1}(x)) = 2\left(\frac{x-3}{2}\right) + 3 f(f−1(x))=(x−3)+3f(f^{-1}(x)) = (x-3) + 3 f(f−1(x))=xf(f^{-1}(x)) = x
  14. Calculate f−1(f(x))f^{-1}(f(x)).

    f−1(f(x))=f−1(2x+3)f^{-1}(f(x)) = f^{-1}(2x+3) f−1(f(x))=(2x+3)−32f^{-1}(f(x)) = \frac{(2x+3)-3}{2} f−1(f(x))=2x2f^{-1}(f(x)) = \frac{2x}{2} f−1(f(x))=xf^{-1}(f(x)) = x
  15. Compare the results.

    Since f(f−1(x))=xf(f^{-1}(x)) = x and f−1(f(x))=xf^{-1}(f(x)) = x, it is proven that f(f−1(x))=f−1(f(x))f(f^{-1}(x)) = f^{-1}(f(x)).

    2.3.6 Draw a neat graph of f(x)f(x) and f−1(x)f^{-1}(x) on the same system of axes on ADDENDUM A (attached), clearly showing the nature of the start and endpoints on the graphs. Also show the line about which f(x)f(x) reflects f−1(x)f^{-1}(x) and label it.

    To draw the graph:

    • Graph of f(x)=2x+3f(x) = 2x+3:

      • Plot the starting point: For x=−1x=-1, f(−1)=2(−1)+3=1f(-1) = 2(-1)+3 = 1. This is a closed circle at (−1,1)(-1, 1) because x≥−1x \ge -1.
      • Plot the ending point: For x=2x=2, f(2)=2(2)+3=7f(2) = 2(2)+3 = 7. This is an open circle at (2,7)(2, 7) because x<2x < 2.
      • Draw a straight line connecting these two points.
    • Graph of f−1(x)=x−32f^{-1}(x) = \frac{x-3}{2}:

      • The domain of f−1(x)f^{-1}(x) is x∈[1,7)x \in [1, 7).
      • Plot the starting point: For x=1x=1, f−1(1)=1−32=−1f^{-1}(1) = \frac{1-3}{2} = -1. This is a closed circle at (1,−1)(1, -1).
      • Plot the ending point: For x=7x=7, f−1(7)=7−32=2f^{-1}(7) = \frac{7-3}{2} = 2. This is an open circle at (7,2)(7, 2).
      • Draw a straight line connecting these two points.
    • Line of reflection:

      • Draw the line y=xy=x. This line acts as the axis of symmetry between f(x)f(x) and f−1(x)f^{-1}(x). Label this line as y=xy=x.
Was this helpful?

Still stuck on this one?

Ask a follow-up, and the answer starts from this question.

Got a different question?Ask your own question