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2 years ago

If y=6 when x=15 then which of thr following is the value of x when y=20

Mathematics

1 answer:

denis23 [38]2 years ago

7 0

Answer:

if you meant x times y...

15 x 20 is 300.

if you meant x + y...

15 + 20 is 35.

if you meant anything else, please let me know

the way it was written confused me but I tried.

You might be interested in

What is the measure of the angle?

AveGali [126]

We know the full protractor measures 180 degrees.

We need to know what angle it is on. By looking at it, it looks like it is on 135.

180-135= 45

The angle is 45 <em>degrees.

I hope this helps!
~kaikers</em>

3 0

3 years ago

Evaluate the integral below, where C is the curver(t) = ‹sin(t),cos(t), sin(2t)›, 0 ≤ t ≤2π. (Hint: Observe that C lies on the s

nordsb [41]

We can compute the integral directly: we have

$\begin{cases}x(t)=\sin t\\y(t)=\cos t\\z(t)=\sin(2t)\end{cases}\implies\begin{cases}\mathrm dx=\cos t\,\mathrm dt\\\mathrm dy=-\sin t\,\mathrm dt\\\mathrm dz=2\cos(2t)\,\mathrm dt\end{cases}$

Then the integral is

$\displaystyle\int_C(y+9\sin x)\,\mathrm dx+(z^2+4\cos y)\,\mathrm dy+x^3\,\mathrm dz$

$=\displaystyle\int_0^{2\pi}\bigg((\cos t+9\sin(\sin t))\cos t-(\sin^2(2t)+4\cos(\cos t))\sin t+\sin^3t\bigg)\,\mathrm dt$

$=\displaystyle\int_0^{2\pi}\cos^2t+9\cos t\sin(\sin t)-\sin^2(2t)\sin t-4\sin t\cos(\cos t)+\sin^3t\,\mathrm dt$

You could also take advantage of Stokes' theorem, which says the line integral of a vector field $\vec F$ along a closed curve $C$ is equal to the surface integral of the curl of $\vec F$ over any surface $S$ that has $C$ as its boundary.

In this case, the underlying field is

$\vec F(x,y,z)=\langle y+9\sin x,z^2+4\cos y,x^3\rangle$

which has curl

$\mathrm{curl}\vec F(x,y,z)=-\langle2z,3x^2,1\rangle$

We can parameterize $S$ by

$\vec s(u,v)=\langle u\cos v,u\sin v,2u^2\cos v\sin v\rangle=\langle u\cos v,u\sin v,u^2\sin(2v)\rangle$

with $0\le u\le1$ and $0\le v\le2\pi$ .

Note that when viewed from above, $C$ has negative orientation (a particle traveling on this path moves in a clockwise direction). Take the normal vector to $S$ to be pointing downward, given by

$\dfrac{\partial\vec s}{\partial v}\times\dfrac{\partial\vec s}{\partial u}=\langle2u^2\sin v,2u^2\cos v,-u\rangle$

Then the integral is

$\displaystyle\int_C\vec F\cdot\mathrm d\vec r=\iint_S\mathrm{curl}\vec F(x,y,z)\cdot\mathrm d\vec S$

$=\displaystyle\int_0^{2\pi}\int_0^1-\langle2u^2\sin(2v),3u^2\cos^2v,1\rangle\cdot\langle2u^2\sin v,2u^2\cos v,-u\rangle\,\mathrm du\,\mathrm dv$

$=\displaystyle-\int_0^{2\pi}\int_0^14u^4\sin(2v)\sin v+6u^4\cos^3v-u\,\mathrm du\,\mathrm dv$

Both integrals are kind of tedious to compute, but personally I prefer the latter method. Either way, you end up with a value of $\boxed\pi$ .

4 0

2 years ago

In a class, 60% of the students are boys and the rest are girls. If the number of boys is 30, how many students are there?

irga5000 [103]

50 total students

20 girls

Explanation:

total students: 100%

----------------

60% → 30

1% → 30/60

1% → 0.5

100% → (0.5 * 100)

100% → 50

number of girls:

total students - number of boys

50 - 30

5 0

2 years ago

Can y’all help me on question 16?!

Zina [86]

600kb in 24 seconds to find out how many kbs per second divide by 24
600/24 is 25kb

6 0

2 years ago

A ball was dropped from a height of 60m. Each time it hit the ground, it bounced up 1/2 (half) of the height that it dropped. Ho

asambeis [7]

Answer:

The ball traveled 116.25 m when it hit the ground for the fifth term

Step-by-step explanation:

This is a geometric progression exercise and what we are asked to look for is the sum of a GP.

The ball was dropped from a height of 60 m. This means that the initial height of the ball is 60 m.

First value, a = 60

Each time it hit the ground, it bounced up 1/2 (half) of the height that it dropped.

This is the common ratio, r = 1/2 = 0.5

The number of terms it hits the ground is the number of terms in the GP.

number of terms, n = 5

The distance traveled by the ball when it hit the ground for the fifth term will be modeled by the equation:

$S_n = \frac{a(1 - r^n) }{1 - r} \\S_5 = \frac{60(1 - 0.5^5) }{1 - 0.5}\\S_5 = \frac{58.125}{0.5} \\S_5 = 116.25 m$

4 0

2 years ago