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3 years ago

What does X equal ????

Mathematics

1 answer:

ivann1987 [24]3 years ago

6 0

Rearrange the formula to get cos(A) = (b^2 + c^2 - a^2) / (2bc)
cos(X) = (20^2 + 18^2 - 22^2) / (2 x 20 x 18) = 0.33333...
X = cos^-1(0.3333...) = 70.5 degrees (1 dp)

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Differentiate Vx(x + 2) with respect to x.

Travka [436]

Answer:

$y'= \frac{3x+2}{2\sqrt{x} }$

General Formulas and Concepts:

Calculus

The derivative of a constant is equal to 0

Basic Power Rule:

f(x) = cxⁿ
f’(x) = c·nxⁿ⁻¹

Product Rule: $\frac{d}{dx} [f(x)g(x)]=f'(x)g(x) + g'(x)f(x)$

Chain Rule: $\frac{d}{dx}[f(g(x))] =f'(g(x)) \cdot g'(x)$

Step-by-step explanation:

Step 1: Define

$y=\sqrt{x} (x+2)$

Step 2: Rewrite

$y=x^{\frac{1}{2} } (x+2)$

Step 3: Differentiate

Product Rule [Basic Power/Chain Rule]: $y'= \frac{1}{2} x^{\frac{1}{2} -1}(x+2)+x^{\frac{1}{2} }(1)$
Simplify: $y'= \frac{1}{2} x^{\frac{-1}{2}}(x+2)+x^{\frac{1}{2}}$
Rewrite: $y'= \frac{x+2}{2\sqrt{x} } + \sqrt{x}$
Add: $y'= \frac{3x+2}{2\sqrt{x} }$

7 0

3 years ago

I am a 2-digit number. If you divide me by 5 then multiply by 2, the I? product is 20. What number am

Kay [80]

So we are going to make this into a equation and evaluate it:
20 = (n ÷ 5) x 2
This is a two-step equation.
First we divide both sides by 2. We now have:10 = n ÷ 5
Then we multiply each side by 5. Now we have the final answer:50 = n
The two-digit number is 50, hope this helps!

4 0

3 years ago

The function f(x)=125(0.9)x models the population of a species of fly in millions after x years.

deff fn [24]

Answer: (B) 3 times as fast

Step-by-step explanation:

rate of change is the "slope" between the given interval.

f(x) = 125(.9)ˣ

f(1) = 125(.9)¹

= 112.5

f(5) = 125(.9)⁵

= 73.8

$\dfrac{f(5) - f(1)}{5 - 1} = \dfrac{73.8-112.5}{5-1} = -\dfrac{38.7}{4} = -9.675$

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f(11) = 125(.9)¹¹

= 39.2

f(15) = 125(.9)¹⁵

= 25.7

$\dfrac{f(15) - f(11)}{15 - 11} = \dfrac{39.2-25.7}{15-11} = -\dfrac{13.5}{4} = -3.375$

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3 years ago

Express 0.1 as a percent.

Zigmanuir [339]

Answer: 10%

Explanation: 0.10=10%

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3 years ago

Read 2 more answers

Explain how you could convert 152 cups into gallons.

Mila [183]

Answer: There are 16 cups in every gallon so we could divide 152 by 16 and get our number of gallons which would give us 9.63 or a little over 9 and a half gallons.

Step-by-step explanation:

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