Answer:
6
Step-by-step explanation:
i'm not really sure but i'm sure it's accurate
<h3>Problem Solution</h3>
Assuming the spool is a cylinder and the circumference we're winding around is that of a circle with the given area, we can write the relation between circumference and area as
... C = 2√(πA)
10 times the circumference is then
... 10C = 20√(π·20 cm²) = 40√(5π) cm ≈ 159 cm
<h3>Formula Derivation</h3>
The usual formulas for circumference and area are
... C = 2πr
... A = πr²
If we multiply the area formula by π and take the square root, we get
... πA = (πr)²
... √(πA) = πr
Multiplying this by 2 gives circumference.
... C = 2√(πA) = 2πr
Answer:
1) ∫ x² e^(x) dx
4) ∫ x cos(x) dx
Step-by-step explanation:
To solve this problem, eliminate the choices that can be solved by substitution.
In the second problem, we can say u = x², and du = 2x dx.
∫ x cos(x²) dx = ∫ ½ cos(u) du
In the third problem, we can say u = x², and du = 2x dx.
∫ x e^(x²) dx = ∫ ½ e^(u) du
In the order of operation, multiplying or dividing don't take preference over the other. So with them, you work from left to right.
This means for this question, you first divide, then multiply.
