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A spherical balloon of radius r cm has volume Vcm^3 , where V =4/3 * pi * r^3. The balloon is inflated at a constant rate of 10 cm^3 s^-1 . Find the rate of increase of r when r = 8.

We are being asked to find the rate of change of radius, dr/dt. We will need to use the chain rule to do this: dV/dt = dV/dr * dr/dt.

We are given that dV/dt is 10cm^3 per second, and differentiati...

MA
Answered by Max A. Maths tutor
14097 Views

Find the roots of y=x^{2}+2x+2

y=x2+2x-3

Can solve using quadratic equation. Using the square method to obtain for the square term and x term (x+1)(x+1) = x2+2x+1

Therefore (x+1)(x+1)-4=y

To f...

HS
Answered by Harry S. Maths tutor
6622 Views

Simplify i^{4}?

Simplify i4?

We know that i = -11/2

Therefore i2=-1

As i4=i2xi2 

Then i4=-1x-1=1

HS
3124 Views

Find the intercept between the two equations below?

y = 2x+5

y=x+1

First equate:       2x+5=x+1

Rearrage for x:    2x-x=1-5

Which gives:       x=-4

HS
Answered by Harry S. Maths tutor
3184 Views

Describe how ventilation of the lungs occurs.

Ventilation is the process of moving air in and out of the lungs. This is brought about by pressure changes in the thoracic cavity. During inspiration, the diaphragm contracts causing it to flatten and mo...

ES
Answered by Emily S. Biology tutor
4389 Views

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