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How do you find the normal to a curve at a given co-ordinate?

You first find the gradient of the tangent to the curve at this given co-ordinate by differentiating the given equation of the curve, and then, assuming the equation of the curve is in terms of x, replacing ...
SI
Answered by Srabon I. Maths tutor
5057 Views

Find the equation of the line that is perpendicular to the line 3x+5y=7 and passes through point (-2,-3) in the form px+qy+r=0

Gradient of line 3x+5y=7: 5y=-3x+7, y=-3/5x+7/5 gradient = -3/5 Gradient of perpendicular line: 5/3 Perpendicular line with points: y+3=5/3(x+2), 3y+9=5(x+2), 3y+9=5x+10, 5x-3y+1=0
PI
Answered by Paul I. Maths tutor
9396 Views

Differentiate y=sin(x)*x^2.

Using the chain rule, we let u = sin(x) and v = x^2. Then dy/dx = u dv/dx + v du/dx. dv/dx = 2x and du/dx = cos(x). So dy/dx = sin(x) 2x + x^2 cos(x).
LM
Answered by Lucy M. Maths tutor
4602 Views

Expand and simplify (5a-2b)(3a-4b)

=(5a x 3a) + (5a x -4b) + (3a x -2b) + (-2b x -4b) =15a^2 - 20ab - 6ab + 8b^2 =15a^2 - 26ab + 8b^2
PI
Answered by Paul I. Maths tutor
11060 Views

Compare the wavelength, frequency and speed of an emitted and reflected microwave

A reflected microwave will have a decreased wavelength, increased frequency and same speed when compared to an emitted microwave.
PI
Answered by Paul I. Physics tutor
4846 Views