Maths Question Help - GCSE!!!
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Maths Question Help - GCSE!!!
Need some help please guys, the wife is helping our niece revise for her gcse but we are struggling to remember these equations......
q1. for the equation, y=5000x - 625 xsquared, find dy/dx?
q2. find the co-ordinates of the turning point on the graph
y=5000x - 625 xsquared
Thanks
Leigh
q1. for the equation, y=5000x - 625 xsquared, find dy/dx?
q2. find the co-ordinates of the turning point on the graph
y=5000x - 625 xsquared
Thanks
Leigh
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Need some help please guys, the wife is helping our niece revise for her gcse but we are struggling to remember these equations......
q1. for the equation, y=5000x - 625 xsquared, find dy/dx?
q2. find the co-ordinates of the turning point on the graph
y=5000x - 625 xsquared
Thanks
Leigh
q1. for the equation, y=5000x - 625 xsquared, find dy/dx?
q2. find the co-ordinates of the turning point on the graph
y=5000x - 625 xsquared
Thanks
Leigh
#15
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iTrader: (11)
y = 5000x - 625x^2
First find dy/dx = 5000-1250x
Now there are turning points when dy/dx = 0, so:
0 = 5000 - 1250x
1250x = 5000
x = 500/125 or 4
To find the y-coordinate of the turning point, put this value of x into the original function:
y = 5000x - 625x^2
= 5000(500/125) - 625 (500/125)^2
=20000 - 10000
= 10000
So there is a turning point at (4, 10000)
I'm pretty sure this is right.
Rich
First find dy/dx = 5000-1250x
Now there are turning points when dy/dx = 0, so:
0 = 5000 - 1250x
1250x = 5000
x = 500/125 or 4
To find the y-coordinate of the turning point, put this value of x into the original function:
y = 5000x - 625x^2
= 5000(500/125) - 625 (500/125)^2
=20000 - 10000
= 10000
So there is a turning point at (4, 10000)
I'm pretty sure this is right.
Rich
#17
PassionFord Post Whore!!
iTrader: (1)
y = 5000x - 625x^2
First find dy/dx = 5000-1250x
Now there are turning points when dy/dx = 0, so:
0 = 5000 - 1250x
1250x = 5000
x = 500/125 or 4
To find the y-coordinate of the turning point, put this value of x into the original function:
y = 5000x - 625x^2
= 5000(500/125) - 625 (500/125)^2
=20000 - 10000
= 10000
So there is a turning point at (4, 10000)
I'm pretty sure this is right.
Rich
First find dy/dx = 5000-1250x
Now there are turning points when dy/dx = 0, so:
0 = 5000 - 1250x
1250x = 5000
x = 500/125 or 4
To find the y-coordinate of the turning point, put this value of x into the original function:
y = 5000x - 625x^2
= 5000(500/125) - 625 (500/125)^2
=20000 - 10000
= 10000
So there is a turning point at (4, 10000)
I'm pretty sure this is right.
Rich
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We are struggling with this part
____________
y = 5000x - 625x^2
First find dy/dx = 5000-1250x
Now there are turning points when dy/dx = 0, so:
0 = 5000 - 1250x
1250x = 5000
x = 500/125 or 4
_____________
We see that you have divided both sides by x, but should it not then be
5000-625x ??
Thanks
leigh
____________
y = 5000x - 625x^2
First find dy/dx = 5000-1250x
Now there are turning points when dy/dx = 0, so:
0 = 5000 - 1250x
1250x = 5000
x = 500/125 or 4
_____________
We see that you have divided both sides by x, but should it not then be
5000-625x ??
Thanks
leigh
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Y = 5000x – 625xsquared
First dy/dx = 0
So divide both side by x
y/x = (5000x / x) – (625x2/x) = 0
cancel the x’s out
0 = 5000 – 625x
Divide all parts by 625
0/625 = (5000/625) – (625x/625)
simplify
0 = 8 – x
Plus x to both sides
X = 8
No substitute x = 8 into original equation
Y = (5000 * 8) – (625 * 8)
Y = 40000 – 5000
Y = 35000
hope this helps
First dy/dx = 0
So divide both side by x
y/x = (5000x / x) – (625x2/x) = 0
cancel the x’s out
0 = 5000 – 625x
Divide all parts by 625
0/625 = (5000/625) – (625x/625)
simplify
0 = 8 – x
Plus x to both sides
X = 8
No substitute x = 8 into original equation
Y = (5000 * 8) – (625 * 8)
Y = 40000 – 5000
Y = 35000
hope this helps
#22
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sry forgot to square 8 on last part of equation, here it is again
Y = 5000x – 625xsquared
First dy/dx = 0
So divide both side by x
y/x = (5000x / x) – (625x2/x) = 0
cancel the x’s out
0 = 5000 – 625x
Divide all parts by 625
0/625 = (5000/625) – (625x/625)
simplify
0 = 8 – x
Plus x to both sides
X = 8
No substitute x = 8 into original equation
Y = (5000 * 8) – (625 * 8squared)
Y = 40000 – 40000
Y = 0
Y = 5000x – 625xsquared
First dy/dx = 0
So divide both side by x
y/x = (5000x / x) – (625x2/x) = 0
cancel the x’s out
0 = 5000 – 625x
Divide all parts by 625
0/625 = (5000/625) – (625x/625)
simplify
0 = 8 – x
Plus x to both sides
X = 8
No substitute x = 8 into original equation
Y = (5000 * 8) – (625 * 8squared)
Y = 40000 – 40000
Y = 0
#23
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iTrader: (4)
Y = 5000x 625xsquared
First dy/dx = 0
So divide both side by x
y/x = (5000x / x) (625x2/x) = 0
cancel the xs out
0 = 5000 625x
Divide all parts by 625
0/625 = (5000/625) (625x/625)
simplify
0 = 8 x
Plus x to both sides
X = 8
No substitute x = 8 into original equation
Y = (5000 * 8) (625 * 8)
Y = 40000 5000
Y = 35000
hope this helps
First dy/dx = 0
So divide both side by x
y/x = (5000x / x) (625x2/x) = 0
cancel the xs out
0 = 5000 625x
Divide all parts by 625
0/625 = (5000/625) (625x/625)
simplify
0 = 8 x
Plus x to both sides
X = 8
No substitute x = 8 into original equation
Y = (5000 * 8) (625 * 8)
Y = 40000 5000
Y = 35000
hope this helps
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We have sussed it out using half your answer and half sonic booms answers
No substitute x = 8 into original equation
Y = (5000 * 8) – (625 * 8)
Y = 40000 – 5000
Y = 35000
hope this helps
You forgot to square the 625 8x ^2
so
40000 - 625 x 64 =y
y = 40000 - 40000 =0
So are we correct in saying
x = 8
y = 0
No substitute x = 8 into original equation
Y = (5000 * 8) – (625 * 8)
Y = 40000 – 5000
Y = 35000
hope this helps
You forgot to square the 625 8x ^2
so
40000 - 625 x 64 =y
y = 40000 - 40000 =0
So are we correct in saying
x = 8
y = 0
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many thanks for the help guys
She is on her way home but is back tomorrow night as we have helped her so much
Stand by for the next installment tomorrow
Thanks
Leigh
She is on her way home but is back tomorrow night as we have helped her so much
Stand by for the next installment tomorrow
Thanks
Leigh
#35
PassionFord Post Whore!!
iTrader: (1)
We are struggling with this part
____________
y = 5000x - 625x^2
First find dy/dx = 5000-1250x
Now there are turning points when dy/dx = 0, so:
0 = 5000 - 1250x
1250x = 5000
x = 500/125 or 4
_____________
We see that you have divided both sides by x, but should it not then be
5000-625x ??
Thanks
leigh
____________
y = 5000x - 625x^2
First find dy/dx = 5000-1250x
Now there are turning points when dy/dx = 0, so:
0 = 5000 - 1250x
1250x = 5000
x = 500/125 or 4
_____________
We see that you have divided both sides by x, but should it not then be
5000-625x ??
Thanks
leigh
5000 - 625^2, ie 5000 - 1250