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3 years ago

13

The current in a stream moves at a speed of 5 km/h. A boat travels 20 km upstream and 20 km downstream in a total of 3 hours. Fi

nd the speed of the boat in still water.

1 answer:

Hatshy [7]3 years ago

5 0

Answer:

14

Step-by-step explanation:

im right

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Please help me answer this math problem

Vesnalui [34]

Answer:

The answer is AAS.

Step-by-step explanation:

Since you have 2 angles that are the same and 1 side which are the same or congruent.

A = E

and C=C they are vertical angles so they are the same

And the AB and ED side are also same.

5 0

3 years ago

What is the inverse of y=pi/2+sin x

Alekssandra [29.7K]

Answer:

$f^{-1}(x)=\sin ^{-1}(x-\frac{\pi}{2})$

Step-by-step explanation:

The given function is

$y=\frac{\pi}{2}+\sin x$

To find the inverse of this function, we interchange x and y.

$x=\frac{\pi}{2}+\sin y$

we now solve for y.

$x-\frac{\pi}{2}=\sin y$

Take the sine inverse of both sides to obtain;

$\sin ^{-1}(x-\frac{\pi}{2})=y$

Hence the inverse of the given function is;

$f^{-1}(x)=\sin ^{-1}(x-\frac{\pi}{2})$

where $\frac{\pi}{2}-1\le x\le \frac{\pi}{2}+1$

6 0

3 years ago

Read 2 more answers

I need this done asap<br>will give brainliest<br>

lapo4ka [179]

2,4 and I am not too sure but I think -4

3 0

3 years ago

What is 2 2/3×3 1/4 as a fraction form

8090 [49]

Answer:

8 2/3

Step-by-step explanation:

2 2/3×3 1/4

Change to improper fractions.

2 2/3=8/3

3 1/4=13/4

8/3x13/4=26/3

=8 2/3

Hope this helps :)

4 0

2 years ago

Read 2 more answers

The following integral requires a preliminary step such as long division or a change of variables before using the method of par

shtirl [24]

Division yields

$\dfrac{x^4+7}{x^3+2x} = x-\dfrac{2x^2-7}{x^3+2x}$

Now for partial fractions: you're looking for constants <em>a</em>, <em>b</em>, and <em>c</em> such that

$\dfrac{2x^2-7}{x(x^2+2)} = \dfrac ax + \dfrac{bx+c}{x^2+2}$

$\implies 2x^2 - 7 = a(x^2+2) + (bx+c)x = (a+b)x^2+cx + 2a$

which gives <em>a</em> + <em>b</em> = 2, <em>c</em> = 0, and 2<em>a</em> = -7, so that <em>a</em> = -7/2 and <em>b</em> = 11/2. Then

$\dfrac{2x^2-7}{x(x^2+2)} = -\dfrac7{2x} + \dfrac{11x}{2(x^2+2)}$

Now, in the integral we get

$\displaystyle\int\frac{x^4+7}{x^3+2x}\,\mathrm dx = \int\left(x+\frac7{2x} - \frac{11x}{2(x^2+2)}\right)\,\mathrm dx$

The first two terms are trivial to integrate. For the third, substitute <em>y</em> = <em>x</em> ² + 2 and d<em>y</em> = 2<em>x</em> d<em>x</em> to get

$\displaystyle \int x\,\mathrm dx + \frac72\int\frac{\mathrm dx}x - \frac{11}4 \int\frac{\mathrm dy}y \\\\ =\displaystyle \frac{x^2}2+\frac72\ln|x|-\frac{11}4\ln|y| + C \\\\ =\displaystyle \boxed{\frac{x^2}2 + \frac72\ln|x| - \frac{11}4 \ln(x^2+2) + C}$

7 0

3 years ago