VCE Maths questions help (1 Viewer)

boredsatan

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A ball flies through the air following the equation y = 2 + 0.12x - 0.002^2. The ground to where the ball lands is modelled by y = 0.15x. The coordinates on the ground where the cannon ball lands is.
Do I need to find the point of intersection of these lines?
 

pikachu975

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A ball flies through the air following the equation y = 2 + 0.12x - 0.002^2. The ground to where the ball lands is modelled by y = 0.15x. The coordinates on the ground where the cannon ball lands is.
Do I need to find the point of intersection of these lines?
I think so but the question is worded weirdly.

Basically if you're stuck with a question, try any method you can think of! Pretend it's like an exam and you have to try something, don't just give up easily and ask others.

Also if there's worked solutions DEFINITELY look at them to see how to do it. Then close the answers and retry the question.
 

boredsatan

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The equation of a straight line which makes an angle of 30 degrees with the positive x axis and cuts the y axis at 5
is this working our right
y - y1=m(x-x1)
y-5=m(x-0)
m = tan theta
m = tan 30 degrees
m = 0.577
y - 5 = 0.577(x-0)
y = 0.577x + 5
 

boredsatan

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show that the graph of f(x) = px^2+ q has no x intercept if pq>0
so ax^2 +c
a*c>0, therefore the y intercept will be higher than 0, therefore there is no x intercept
Is this above working out correct?
 

InteGrand

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show that the graph of f(x) = px^2+ q has no x intercept if pq>0
so ax^2 +c
a*c>0, therefore the y intercept will be higher than 0, therefore there is no x intercept
Is this above working out correct?
No
 

boredsatan

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show that y = 4-6x+2x^2+3x^3 has exactly one x intercept
factorise it
(x+2)(3x^2-4x+2)
b^2 - 4ac = 0
16-4(3)(2) =
16-24 = -8
Not sure how to finish it
 

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