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3 years ago

The price of a car was decreased by 9% to £14000. What was the price before the decrease?

Mathematics

1 answer:

zaharov [31]3 years ago

7 0

Answer: 15,384.60 is the price before the car was decreased by 9%.

You can verify this by doing the following:

15,384.60 x 9% (.09) = 1,384.615

15,384.60 (original price) - 1,384.614 (9% of original price) = 13,999.986 which is rounded to 14,000.00.

Therefore, the answer of 15,384.60 is correct.

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3 years ago

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<u>Solution-</u>

As the equation of the cylinder is in rectangular for, so we have to convert it into parametric form with

x = cos t, y = 2 sin t (∵ 4x² + y² = 4 ⇒ 4cos²t + 4sin²t = 4, then it will satisfy the equation)

Then, substituting these values in the plane equation to get the z parameter,

cos t + 2sin t + z = 2

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$\frac{dz}{dt} = \sin t-2cos t$

As it is a full revolution around the original cylinder is from 0 to 2π, so we have to integrate from 0 to 2π

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$=\int_{0}^{2\pi}\sqrt{(-\sin t)^{2}+(2\cos t)^{2}+(\sin t-2\cos t)^{2}$

$=\int_{0}^{2\pi}\sqrt{(2\sin t)^{2}+(8\cos t)^{2}-(4\sin t\cos t)$

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3 years ago

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vlada-n [284]

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We start with Left hand side

We know that csc(x) = 1/ sin(x)

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$4 \frac{1}{sin(2x)}$

Also we use identity

sin(2x) = 2 sin(x) cos(x)

$4 \frac{1}{2sin(x)cos(x)}$

4 divide by 2 is 2

Now we multiply top and bottom by sin(x) because we need tan(x) in our answer

$2\frac{1*sin(x)}{sin(x)cos(x)*sin(x)}$

$2\frac{sin(x)}{sin^2(x)cos(x)}$

$2\frac{1}{sin^2(x)} \frac{sin(x)}{cos(x)}$

We know that sinx/ cosx = tan(x)

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3 years ago

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9514 1404 393

Answer:

see attached

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Find the y-values corresponding to x-values of 0 and 1, then plot those points and draw a line through them.

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The attached graph shows these points and the line through them.

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Answer:

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Step-by-step explanation:

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