Answer:
11 pies
Step-by-step explanation:
100-12=88
88/8=11
1/2×4=4/8
1/8=1/8
1/4×2=2/8
so 4/8+2/8=6/8
and 6/8+1/8=7/8
so 7/8 ribbons will be collected
2 x 3 = 6
6 x 3 = 18
18 x 3 = 54
The answer is 54
Answer:
Step-by-step explanation:
<span>since sin and cos = each other at pi/4; take your integrals from 0 to pi/4
</span><span>[S] cos(t) dt - [S] sin(t) dt ;[0,pi/4]
</span>
<span>to revolve it around the x axis;
we do a sum of areas
[S] 2pi [f(x)]^2 dx
</span>
<span>take the cos first and subtract out the sin next; like cutting a hole out of a donuts.
</span><span>pi [S] cos(x)^2 dx - [S] sin(x)^2 dx ; [0,pi/4]
</span>
<span>cos(2t) = 2cos^2 - 1
cos^2 = (1+cos(2t))/2
</span>
<span>1/sqrt(2) - (-1/sqrt(2) +1)
1/sqrt(2) + 1/sqrt(2) -1
(2sqrt(2) - sqrt(2))/sqrt(2) = sqrt(2)/sqrt(2) = 1</span>
