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Sketch the graph y= x^2- 4x+2

User Ssierral
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1 Answer

4 votes

Answer:

Explanation:

The graph of this is a parabola.

One way to do it is to first convert to vertex form

y = x^2 - 4x + 2

= (x - 2)^2 - 4 + 2

= (x - 2)^2 - 2.

So there is a minimum point at (2, -2)

( its a minimum because the coefficient of x^2 is positive (+1).

The graph will be symmetrical about the vertical line x = 2.

Also when x = 0, y = (-2)^2 - 2 = 2, so the graph passes through (0, 2) on y-axis.

Now we find the points where the graph passes through the x-axis.

(x - 2)^2 - 2. = 0

(x - 2)^2 = 2

x-2 = +/- √2

x = 2 +/- √2

= 3.41 and o.59

These are the points (0.59), 1) and (3.41, 0).

So the graph passes through these points.

So we have 4 points which are on the graph and we know its symetrical about the line x = 2, so we can sketch it . Its shaped a little like a U.

User Shyam Kumar
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7.2k points