The surface area of the cylinder is 301.44
Answer: less than
Step-by-step explanation:
If <em>x</em>² + <em>y</em>² = 1, then <em>y</em> = ±√(1 - <em>x</em>²).
Let <em>f(x)</em> = |<em>x</em>| + |±√(1 - <em>x</em>²)| = |<em>x</em>| + √(1 - <em>x</em>²).
If <em>x</em> < 0, we have |<em>x</em>| = -<em>x</em> ; otherwise, if <em>x</em> ≥ 0, then |<em>x</em>| = <em>x</em>.
• Case 1: suppose <em>x</em> < 0. Then
<em>f(x)</em> = -<em>x</em> + √(1 - <em>x</em>²)
<em>f'(x)</em> = -1 - <em>x</em>/√(1 - <em>x</em>²) = 0 → <em>x</em> = -1/√2 → <em>y</em> = ±1/√2
• Case 2: suppose <em>x</em> ≥ 0. Then
<em>f(x)</em> = <em>x</em> + √(1 - <em>x</em>²)
<em>f'(x)</em> = 1 - <em>x</em>/√(1 - <em>x</em>²) = 0 → <em>x</em> = 1/√2 → <em>y</em> = ±1/√2
In either case, |<em>x</em>| = |<em>y</em>| = 1/√2, so the maximum value of their sum is 2/√2 = √2.
X = k x y
21 = k x 3
k = 7
x = 7y
x = 7(10)
x = 70
Answer:
h = 6
Step-by-step explanation:
Given he area of the banner expressed as;
A = ℎ(2ℎ−2)
h is the height of the banner
A is the area = 60
Substitute
60 = ℎ(2ℎ−2)
60 = 2h² - 2h
30 = h² - h
h²-h-30 = 0
Factorize;
h²-6h+5h-30 = 0
h(h-6)+5(h-6) = 0
(h-6)(h+5) = 0
h - 6 = 0 and h+5 = 0
h = 6 and -5
Since the height cannot be negative;
h = 6
Hence he height of the banner is 6
