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secondary 4 | A Maths
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Christine Goh
Christine Goh

secondary 4 chevron_right A Maths

I do not know how to do this qn. Thanks

Date Posted: 2 years ago
Views: 114

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Ang Yew Keong
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Tan Wee Leng
Tan Wee Leng
2 years ago
Final answer on the rate of change of perimeter is incorrect.

The working on finding the rate of change of x is done correctly.
However, the perimeter being a function of x is not considered.

Perimeter is 10x,
dP/dt = (dP/dx)*(dx/dt)
= (10)*(1cm/s) = 10cm/s

(the units for dA/dx found in this answer should be cm instead)