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3 years ago

Halp me plez I dont wanna fail ( MUST BE A EXPRESSION)

Mathematics

1 answer:

Scilla [17]3 years ago

4 0

Answer:

2x+15=33

Step-by-step explanation:

Let n be the number of days he has been doing sit ups, not counting the first day. Since he does 2 more sit-ups for each day, then the number of additional sit-ups is 2n.

Since he started doing 15 sit-ups on the first day, the total number of sit-ups

after x days would be 2n+15.

Since he did a total of 33 sit ups today, then 2n+15=33

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How do I differentiate this?

disa [49]

Answer:

$\frac{8}{\left(-x+2\right)^2}$ & $x = 1, x = 3$

Step-by-step explanation:

I'm sure you are familiar with the product rule,

If y = u*v => dy/dx = u * dv/dx + v * dy/dx <----- product rule

In this case:

$u=3x+2,\:v=\left(2-x\right)^{-1},\\=>\frac{d}{dx}\left(3x+2\right)\left(2-x\right)^{-1}+\frac{d}{dx}\left(\left(2-x\right)^{-1}\right)\left(3x+2\right)$

Now remember the sum rule:

$\frac{d}{dx}\left(3x+2\right) = \frac{d}{dx}\left(3x\right)+\frac{d}{dx}\left(2\right),\\\frac{d}{dx}\left(3x\right) = 3,\\\frac{d}{dx}\left(2\right) = 0\\\frac{d}{dx}\left(3x+2\right) = 3$

For this second bit we apply the chain rule:

$\frac{d}{dx}\left(\left(2-x\right)^{-1}\right) = -\frac{1}{\left(2-x\right)^2}\frac{d}{dx}\left(2-x\right),\\\frac{d}{dx}\left(2-x\right) = -1,\\\\=> -\frac{1}{\left(2-x\right)^2}\left(-1\right)\\=> \frac{1}{\left(2-x\right)^2}$

If we substitute these values back into the expression... $\frac{d}{dx}\left(3x+2\right)\left(2-x\right)^{-1}+\frac{d}{dx}\left(\left(2-x\right)^{-1}\right)\left(3x+2\right)$

...we get the following:

$3\left(2-x\right)^{-1}+\frac{1}{\left(2-x\right)^2}\left(3x+2\right)$

The rest is just pure simplification:

$3\left(2-x\right)^{-1}+\frac{1}{\left(2-x\right)^2}\left(3x+2\right)\\= \frac{3}{-x+2}+\frac{3x+2}{\left(-x+2\right)^2}\\= \frac{3\left(-x+2\right)}{\left(-x+2\right)^2}+\frac{3x+2}{\left(-x+2\right)^2}\\\\= \frac{3\left(-x+2\right)+3x+2}{\left(-x+2\right)^2}\\\\= \frac{8}{\left(-x+2\right)^2}$

Now let's equate this to equal 8 for the second bit and solve for x:

$\frac{8}{\left(-x+2\right)^2}=8,\\\frac{8}{\left(-x+2\right)^2}\left(-x+2\right)^2=8\left(-x+2\right)^2,\\8=8\left(-x+2\right)^2,\\\left(-x+2\right)^2=1,\\x = 1, x = 3$

4 0

3 years ago

Helppppppppp pleaseee

shutvik [7]

The rate of change is +2

as an ordered pair it would be (1,-3),(2,-1)(3,1),(4,3)

4 0

3 years ago

Read 2 more answers

Make m the subject of g-3m=am+5

Salsk061 [2.6K]

Answer:

m = (g - 5) / (a + 3)

Step-by-step explanation:

g-3m=am+5

Get all the m's on one side.

g - 5 = am + 3m

Combine the m's into one term, using brackets

g - 5 = (a + 3)m

Get m on it's own by dividing by a + 3

(g - 5) / (a + 3) = m

8 0

2 years ago

Read 2 more answers

Find two numbers that multiply to -72 and add up to -1

Andrews [41]

Answer:

-8 and 9

Step-by-step explanation:

-8 x 9 = -72

and -8 + 9 = 1

7 0

2 years ago

How do you find the percent of a number?

Tom [10]

Answer:

(hope this helps can i plz have brainlist :D hehe)

Step-by-step explanation:

How to Calculate Percentages

There are many formulas for percentage problems. You can think of the most basic as X/Y = P x 100. The formulas below are all mathematical variations of this formula.

Let's explore the three basic percentage problems. X and Y are numbers and P is the percentage:

Find P percent of X

Find what percent of X is Y

Find X if P percent of it is Y

Read on to learn more about how to figure percentages.

1. How to calculate percentage of a number. Use the percentage formula: P% * X = Y

Example: What is 10% of 150?

Convert the problem to an equation using the percentage formula: P% * X = Y

P is 10%, X is 150, so the equation is 10% * 150 = Y

Convert 10% to a decimal by removing the percent sign and dividing by 100: 10/100 = 0.10

Substitute 0.10 for 10% in the equation: 10% * 150 = Y becomes 0.10 * 150 = Y

Do the math: 0.10 * 150 = 15

Y = 15

So 10% of 150 is 15

Double check your answer with the original question: What is 10% of 150? Multiply 0.10 * 150 = 15

2. How to find what percent of X is Y. Use the percentage formula: Y/X = P%

Example: What percent of 60 is 12?

Convert the problem to an equation using the percentage formula: Y/X = P%

X is 60, Y is 12, so the equation is 12/60 = P%

Do the math: 12/60 = 0.20

Important! The result will always be in decimal form, not percentage form. You need to multiply the result by 100 to get the percentage.

Converting 0.20 to a percent: 0.20 * 100 = 20%

So 20% of 60 is 12.

Double check your answer with the original question: What percent of 60 is 12? 12/60 = 0.20, and multiplying by 100 to get percentage, 0.20 * 100 = 20%

3. How to find X if P percent of it is Y. Use the percentage formula Y/P% = X

Example: 25 is 20% of what number?

Convert the problem to an equation using the percentage formula: Y/P% = X

Y is 25, P% is 20, so the equation is 25/20% = X

Convert the percentage to a decimal by dividing by 100.

Converting 20% to a decimal: 20/100 = 0.20

Substitute 0.20 for 20% in the equation: 25/0.20 = X

Do the math: 25/0.20 = X

X = 125

So 25 is 20% of 125

Double check your answer with the original question: 25 is 20% of what number? 25/0.20 = 125

Remember: How to convert a percentage to a decimal

Remove the percentage sign and divide by 100

15.6% = 15.6/100 = 0.156

Remember: How to convert a decimal to a percentage

Multiply by 100 and add a percentage sign

0.876 = 0.876 * 100 = 87.6%

(hope this helps can i plz have brainlist :D hehe)

4 0

2 years ago

Read 2 more answers