9514 1404 393
Answer:
a = $0.95
Step-by-step explanation:
The cost of a sharpener is 'a', and the cost of a folder is $2.80 more, so is a+2.80. The total cost of 4 sharpeners and 7 folders is ...
4a +7(a+2.80) = 30.05
11a = 10.45 . . . . . . . . . . . subtract 19.60
a = 0.95 . . . . . . . . . . . divide by 11
The cost of a sharpener is a = $0.95.
(Простите, пожалуйста, мой английский. Русский не мой родной язык. Надеюсь, у вас есть способ перевести это решение. Если нет, возможно, прилагаемое изображение объяснит достаточно.)
Use the shell method. Each shell has a height of 3 - 3/4 <em>y</em> ², radius <em>y</em>, and thickness ∆<em>y</em>, thus contributing an area of 2<em>π</em> <em>y</em> (3 - 3/4 <em>y</em> ²). The total volume of the solid is going to be the sum of infinitely many such shells with 0 ≤ <em>y</em> ≤ 2, thus given by the integral
Or use the disk method. (In the attachment, assume the height is very small.) Each disk has a radius of √(4/3 <em>x</em>), thus contributing an area of <em>π</em> (√(4/3 <em>x</em>))² = 4<em>π</em>/3 <em>x</em>. The total volume of the solid is the sum of infinitely many such disks with 0 ≤ <em>x</em> ≤ 3, or by the integral
Using either method, the volume is 6<em>π</em> ≈ 18,85. I do not know why your textbook gives a solution of 90,43. Perhaps I've misunderstood what it is you're supposed to calculate? On the other hand, textbooks are known to have typographical errors from time to time...
Answer:
B.
Step-by-step explanation:
Irrational as π is irrational.
It goes by 8!
If u see, 4 + 8= 12 +(another) 8 = 20! It skips 8 every time!
If u were to continue it, 20 + 8 = 28 and so on!
The difference is the sum of the number totalled.
Hope this helps!