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Easy question - please help!

Easy question - please help!-example-1
User Cansik
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1 Answer

3 votes

Answer:

a)

A (1, 0)
B (3,0)

b)

P(0,3)

c)

Q(2, -1)

Explanation:

The equation (x-1)(x-2) is a quadratic equation and represents the equation of a parabola

Part a)

The x-intercepts at A and B represent the zeros of the function

Set (x-1)(x-3) = 0 ===> x = 1 and x =3

So the x-intercepts which are the x values at y = 0 are
A(1, 0) and B(3,0)

Part b

P is the y intercept and can be obtained by setting x = 0 and solving for y
==> y = (0-1)(0-3) = -1 x -3 = 3

So P(0, 3)

Part c

Q is the vertex of the parabola and represents a minimum point for the graph

The minimum value for x can be found by differentiation the function with respect to x and setting it equal to 0 and solving for x value

We have y = (x-1)(x-3) = x² -1x - 3x + 3 using the FOIL method

y = x² - 4x + 3

dy/dx = 2x -4

Setting dy/dx = 0

==> 2x - 4 = 0

x2x = 4

x = 2

So the minimum occurs when x = 2

At x = 2,

y = (2-1)(2-3) = 1 x -1 = -1

So the vertex is at (2, -1) which is point Q

User DavedCusack
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7.8k points