Step-by-step explanation:
S = ∫ 2π y ds
ds = √(1 + (dx/dy)²) dy
ds = √(1 + (8y)²) dy
ds = √(1 + 64y²) dy
S = ∫₁² 2π y √(1 + 64y²) dy
S = π/64 ∫₁² 128y √(1 + 64y²) dy
S = π/64 [⅔ (1 + 64y²)^(³/₂)] |₁²
S = π/96 (1 + 64y²)^(³/₂) |₁²
S = π/96 (1 + 256)^(³/₂) − π/96 (1 + 64)^(³/₂)
S = π/96 (257√257) − π/96 (65√65)
S = π/96 (257√257 − 65√65)
Answer:
B. 25%
Step-by-step explanation:
25 percent of 60 would be 15, then if you subtract 15 from 60, you end up with 45, meaning that 25 percent was subtracted.
Pizza I think, but I might have done the math wrong.
Answer:
20/1=20 1 hour read one book
Step-by-step explanation:
4 chapter read in 4 hour because 1 chapter read in one gour
