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3 years ago

BRAINLY FOR THE FASTEST WITH GOOD EXPLANATIONS

Mathematics

1 answer:

Neporo4naja [7]3 years ago

4 0

So, when we're tasked with things like this, rewriting everything in terms of sine and cosine and combining fractions often trivializes things, so doing just that gives us:

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

So out expression is 1/cos(x).

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Which absolute value represents a number less than |−0.14|

jasenka [17]

Answer:

See explanation

Step-by-step explanation:

The given absolute value is

$| - 0.14|$

When we simplify this we get:

$| - 0.14| = 0.14$

Any absolute value expression whose value is less than 0.14 is a solution.

For instance :

$| - 0.1|$

$|0.05|$

$| - 0.006|$

are all less than the 0.14

Since you haven't provided the options, we can't provide an exact answer.

Please remember to post a complete question next time.

3 0

3 years ago

Heidi is driving 200 miles. She has finished 80% of the drive. How many miles is 80% of Heidi's drive.

algol [13]

Answer:

160 miles

Step-by-step explanation:

200 * 0.8 is 160

3 0

3 years ago

Read 2 more answers

Hi can some please help?

Oduvanchick [21]

So I'm assuming that you're taking Calculus.
The first thing you want to do is take the integral of f(x)...
Use the power rule to get:
4X^2-13X+3.
Now solve for X when f(x)=0. This is because when the slope is 0, it is either a minimum or a maximum(I'm assuming you know this)
Now you get X=0.25 and X=3. Since we are working in the interval of (1,4), we can ignore 0.25
Thus our potential X values for max and min are X=1,X=4,X=3(You don't want to forget the ends of the bounds!)
Plugging these value in for f(x), we get
f(1)=2.833
f(3)=-8.5
f(4)=1.667
Thus X=1 is the max and X=3 is the min.
So max:(1,2.833)
min:(3,-8.5)

Hope this helps!

3 0

3 years ago

Find the Fourier series of f on the given interval. f(x) = 1, ?7 < x < 0 1 + x, 0 ? x < 7

Zolol [24]

$f(x)=\begin{cases}1&\text{for }-7$

The Fourier series expansion of $f(x)$ is given by

$\dfrac{a_0}2+\displaystyle\sum_{n\ge1}a_n\cos\frac{n\pi x}7+\sum_{n\ge1}b_n\sin\frac{n\pi x}7$

where we have

$a_0=\displaystyle\frac17\int_{-7}^7f(x)\,\mathrm dx$
$a_0=\displaystyle\frac17\left(\int_{-7}^0\mathrm dx+\int_0^7(1+x)\,\mathrm dx\right)$
$a_0=\dfrac{7+\frac{63}2}7=\dfrac{11}2$

The coefficients of the cosine series are

$a_n=\displaystyle\frac17\int_{-7}^7f(x)\cos\dfrac{n\pi x}7\,\mathrm dx$
$a_n=\displaystyle\frac17\left(\int_{-7}^0\cos\frac{n\pi x}7\,\mathrm dx+\int_0^7(1+x)\cos\frac{n\pi x}7\,\mathrm dx\right)$
$a_n=\dfrac{9\sin n\pi}{n\pi}+\dfrac{7\cos n\pi-7}{n^2\pi^2}$
$a_n=\dfrac{7(-1)^n-7}{n^2\pi^2}$

When $n$ is even, the numerator vanishes, so we consider odd $n$ , i.e. $n=2k-1$ for $k\in\mathbb N$ , leaving us with

$a_n=a_{2k-1}=\dfrac{7(-1)-7}{(2k-1)^2\pi^2}=-\dfrac{14}{(2k-1)^2\pi^2}$

Meanwhile, the coefficients of the sine series are given by

$b_n=\displaystyle\frac17\int_{-7}^7f(x)\sin\dfrac{n\pi x}7\,\mathrm dx$
$b_n=\displaystyle\frac17\left(\int_{-7}^0\sin\dfrac{n\pi x}7\,\mathrm dx+\int_0^7(1+x)\sin\dfrac{n\pi x}7\,\mathrm dx\right)$
$b_n=-\dfrac{7\cos n\pi}{n\pi}+\dfrac{7\sin n\pi}{n^2\pi^2}$
$b_n=\dfrac{7(-1)^{n+1}}{n\pi}$

So the Fourier series expansion for $f(x)$ is

$f(x)\sim\dfrac{11}4-\dfrac{14}{\pi^2}\displaystyle\sum_{n\ge1}\frac1{(2n-1)^2}\cos\frac{(2n-1)\pi x}7+\frac7\pi\sum_{n\ge1}\frac{(-1)^{n+1}}n\sin\frac{n\pi x}7$

3 0

3 years ago

Help me asap!!!!!!!!!!!

melisa1 [442]

Answer:

(x-2)^2-11

Step-by-step explanation:

3 0

3 years ago

Read 2 more answers