Applications of integration :
the line segment x=1-y , 0

Question

Applications of integration :
the line segment x=1-y ,  0 <or equal x <or equal 1 is revolved about the y-axis to generate a cone . find its LATERAL surface area.

anonymous · Answer

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S=pi.1.sqrt(2)

anonymous · Answer

I am supposed to use integration to solve ,, for surface area $$s=2\pi \int\limits_{a}^{b} X dL$$ but I guess we need to edit this equation to calculate the lateral surface area but I don't know what is it??

anonymous · Answer

The area of the curved (lateral) surface of a cone = πrl

I guess I'll remove the 2 from the equation right ? in order to calculate it

anonymous · Answer

hum, i dont remeber it

anonymous · Answer

i will look in my calc book

anonymous · Answer

I calculated it and figured out it is the same I misunderstood something Thank you
the 2 pi in the equation is the revolution of the area it means it will revolve one complete revolution 
THANKS

anonymous · Answer

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