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Please help fast!!! Need this answer to move on!

sketch the graph. write the domain and range

Please help fast!!! Need this answer to move on! sketch the graph. write the domain-example-1

2 Answers

4 votes

Vertex form of parabola

  • y =a(x-h)²+k

where (h,k) is vertex

here it's upward facing parabola so a is positive

  • vertex at (1,-3)

Now equation

  • y=a(x-1)²-3

We need a now

Find a point let it be (3,-1)

Put in equation

  • -1=a(3-1)²-3
  • 2=4a
  • a=1/2

Let's verify once

  • y=1/2(x-1)²-3

Put (-1,-1)

  • -1=1/2(-2)²-3
  • 2=1/2(4)
  • 2=2

Verified

Now

the equation is

  • y=1/2(x-1)²-3

Domain:

  • Domain is set of x values

Here x can be any real no

  • So domain is R

Range:

  • Range is set of y values

Put x=1 for maximum value[ because (x-1)² is always +ve]

  • y=-3

So range

  • [-3,oo)

User Daniel Zeitlin
by
8.7k points
4 votes

Answer:

Domain: (-∞, ∞)

Range: [-3, ∞)

Explanation:

Domain

The domain of a function is the set of all possible input values (x-values) for which the function is defined.

A quadratic function, represented by a parabola with a vertical axis of symmetry, has a domain that includes all real values of x, meaning it is defined for all values of x. The given graph shows an upward-opening parabola. Therefore, the domain of the graph is (-∞, ∞).

Range

The range of a function is the set of all possible output values (y-values) for which the function is defined.

The range of an upward-opening parabola is all real numbers greater than or equal to the y-coordinate of the vertex. The vertex of an upward-opening parabola is the point where the parabola reaches its minimum value (lowest point). From observation of the given graph, the y-coordinate of the vertex is y = -3. Therefore, the range of the graph is [-3, ∞).


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Additional Notes

Note that the equation of the graphed parabola is:


\textsf{Vertex form:} \quad y=(1)/(2)(x-1)^2-3


\textsf{Standard form:} \quad y=(1)/(2)x^2-x-(5)/(2)

User Sravan Kumar
by
8.8k points