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Consider a cone of vertical height H (in metres) and base radius R (in metres) which is full with water. The cone, at time t=0, starts to leak such that it loses water at a rate of k m^3 per second. Give an expression for the rate of change of H.

L = (H 2 +R 2 ) 1/2 V = (1/3)πR 2 (H 2 +R 2 ) 1/2 dV/dt = -k dH/dt = dH/dV × dv/dt dV/dH = (1/3)πR 2 H(H 2 +R 2 ) 1/2 Thus, dH/dt = -3k/(πR 2 H(H 2 +R 2 ) 1/2 ) ​​​​​ ​​​​ ​​
CE
Answered by Callum E. Maths tutor
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Integrate the following function: f(x) = ln(x)

∫ln(x)dx = xln(x) - ∫x/x dx = xln(x) - x + C
CE
Answered by Callum E. Maths tutor
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Solve the simultaneous equations 3x+5y=7, 2x-3y=11

Multiply the first equation by 2, and the second by 3: 6x+10y=14 6x-9y=33 Subtract the second from the first: 19y=-19 solve for y: y=-1 plug in to first equation and solve for x: 6x+10*(-1)=14 6x=24 x=4
JB
Answered by Jamie B. Maths tutor
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Why is the differential of a constant zero?

Any constant (say k) can be rewritten as kx 0 since x 0 =1. When you differentiate this, the 0 which is the power of the x term gets dragged to the front and is multiplied with the rest of the expression (ac...
JC
Answered by Jawad C. Maths tutor
4371 Views

How do you check if a graph ever touches the x-axis?

At the x-axis, y is always zero at any point. If you want to fnd out whether or not a graph reaches the x-axis, then substitute y=0 into the equation and find the value of x. If it solves, then we know it do...
JC
Answered by Jawad C. Maths tutor
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