## Question

secondary 4 | A Maths

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##### Kathy2

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Thank you

Date Posted: 1 month ago
Views: 14

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1st
Here
Date Posted: 1 month ago
Kathy2
1 month ago
where u get 4x?
Eric Nicholas K
1 month ago
Wait let me check
Eric Nicholas K
1 month ago
Dy/dx represents the gradient, which is essentially m in the equation y = mx + c. Remember that tangents are straight lines. So does normals.
Kathy2
1 month ago
I forget
Eric Nicholas K
1 month ago
So here the gradient of the tangent is 4 which means that the equation of the line is y = 4x + c
Eric Nicholas K
1 month ago
Normals are just lines which are perpendicular to tangents, so the normal has gradient -1/4 in this case, so the normal has equation y = -1/4 x + c.
Kathy2
1 month ago
Sorry still confused
Kathy2
1 month ago
Qns don’t have any 4
Eric Nicholas K
1 month ago
Ok I write up the entire thing once again with more explanations, wait
Eric Nicholas K
1 month ago
The 4 comes from the dy/dx value when x = 2. The terms m (in y = mx + c), gradient and dy/dx all mean the same thing.