Answer:
y = 
Step-by-step explanation:
Given that y varies inversely with x then the equation relating them is
y =
← k is the constant of variation
To find k use the condition y =
when x =
, thus
=
= 2k ( divide both sides by 2 )
k = 
y =
← equation of variation
When x =
, then
y =
=
= 
Answer:

Step-by-step explanation:
given,
y=5√sinx
Volume of the solid by revolving

a and b are the limits of the integrals
now,



![V =25\pi [-cos x]_{\pi/4}^{\pi/2}](https://tex.z-dn.net/?f=V%20%3D25%5Cpi%20%5B-cos%20x%5D_%7B%5Cpi%2F4%7D%5E%7B%5Cpi%2F2%7D)
![V =25\pi [-cos (\pi/2)+cos(\pi/4)]](https://tex.z-dn.net/?f=V%20%3D25%5Cpi%20%5B-cos%20%28%5Cpi%2F2%29%2Bcos%28%5Cpi%2F4%29%5D)
![V =25\pi [0+\dfrac{1}{\sqrt{2}}]](https://tex.z-dn.net/?f=V%20%3D25%5Cpi%20%5B0%2B%5Cdfrac%7B1%7D%7B%5Csqrt%7B2%7D%7D%5D)

volume of the solid generated is equal to 
Step-by-step explanation:
look at the picture !
she has to paint actually 6 rectangles :
the 3 tops of the 3 stairs.
and the 3 vertical front boards (the front of each step of the stairs).
what is the area of these rectangles ? summing up all 6 - that is the surface area to be painted.
each top rectangle is clearly
82×19 (19 cm deep) = 1558 cm²
each front board is
82×12 (12 cm high) = 984 cm²
so, in total we have
3×1558 + 3×984 = 4674 + 2952 = 7626 cm²
as surface area to be painted.
Answer:
Step-by-step explanation:
11
Can’t help if there’s no figure