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Please help me with this question urgently! Thanks in advance.​

Please help me with this question urgently! Thanks in advance.​-example-1
User Gu XiaoWan
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1 Answer

3 votes

Explanation:

First. plug in values of x and try to form a curve. Since this a quadratic, we will get a parabola( a U shaped graph).

Plug in values from -3 to 4.

for x.


f( - 3) = 2( - 3) {}^(2) - 3( - 3) - 5 = 22


f( - 2) = 2( - 2) {}^(2) - 3( - 2) - 5 = 9


f( - 1) = 2 + 3 - 5 = 0

Keep going until you get until you get to 4 for x.

The graph above should be your curve.

1. The roots of a quadratic are the x values when y=0, here it is 2.5 and -1.

2. Since the leading degree coeffecient is positive, we have a minimum value. It hard to tell the minimum here so let put this in vertex form, we have


2{x}^(2) - 3x - 5

First. we do


( - b)/(2a)


( - ( - 3))/(4)


= (3)/(4)

Now, we plug that in to find our y intercept of the minimum.


2( (3)/(4) ) {}^(2) - 3( (3)/(4) ) - 5 = (18)/(16) - (9)/(4) - 5 = - ( 18)/(16) - 5 = - (98)/(16)

So we have

(3/4,-98/16).

or

(3/4,-6.125).

Please help me with this question urgently! Thanks in advance.​-example-1
User Piero Macaluso
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3.4k points