All Answers 358196 Answers

Oh. Thanks.

Solve for r:
E/e = (r + R)/(R - r)

E/e = (r + R)/(R - r) is equivalent to (r + R)/(R - r) = E/e:
(r + R)/(R - r) = E/e

Cross multiply:
e (r + R) = E (R - r)

Expand out terms of the left hand side:
e r + e R = E (R - r)

Expand out terms of the right hand side:
e r + e R = E R - E r

Subtract e R - E r from both sides:
r (E + e) = E R - e R

Divide both sides by E + e:
Answer: | r = (E R - e R)/(E + e)=R[E - e] / [E + e]

The height ,H,  is given by :

H  =  3000*sin (15°)  ≈  776.5  m

sec (3x)   = 2

This happens where   cos (3x)  =  1/2

So  3x   =    pi/3   +  2 pi *n         and    3x   =  5pi / 3  + 2pi*n   where n is an integer

Dividing both sides by 3, we have that

x  =  pi/9 + (2/3)pi*n    and   x   =  5pi/ 9  + (2/3)pi*n      where n is an integer

sin (7x)   =  -sqrt (3) / 2

Note

sin (7x )  =   -sqrt (3) / 2  when either

7x    =  4 pi / 3   + 2pi*n    or     7x    =   5 pi/ 3  +  2pi *n   where n is an integer

Dividing both by 7, then

x  = 4 pi / 21 +  (2pi/7)n        or   x  =  5 pi/ 21  + (2p/7)n     where n is an integer

Good work Hectictar :)

There is no way I could read this question, it was just too small.

sin^2(x) + cos(x) + 1 = 0 In the interval [0, 2π)

\(sin^2(x) + cos(x) + 1 = 0 \\ -cos^2(x) + cos(x) + 2= 0\\ cos^2(x) - cos(x) - 2= 0\\ let\;\;t=cos(x)\\ t^2-t-2=0\\ (t-2)(t+1)=0\\ t=2\;\;or\;\;t=-1\\ -1\le t \le 1\\ so\;\; t=-1\\ cos(x)=-1\\ x=\pi \)

I got pretty close, does it have to be exact?

3 cot^2(x) − 1 = 0       add 1 to both sides

3 cot^2 (x)   =  1       divide both sides by 3

cot^2( x)  =   1/3       take the square root of both sides

cot (x)  =  ±√ (1/3)   = 

So

cot (x)  = √ (1/3)      and this happens at  pi/ 3   +  pi* n    where n is an integer

And

cot (x)  =  - √1/3)    and this   happens  at     -pi/3  +  pi*n   where n is an integer

Can I use multiple element equations?

3 lbs

0.9136212624584718

4.440625 *10^27

3.5   + 2.7  + 1.9.......

The common difference is  - .8

The 30th term, a₃₀,  is given by  :

a₃₀   =  3.5 - .8(29)   =  -19.7

And the sum  is given by

[a₁ + a₃₀] * n / 2           where  a₁   =  3.5,   a₃₀  =  -19.7    and n   = 30

[ 3.5 +   -19.7] * 30 / 2   =   -243

To isolate x we can use the tangent inverse  ( the "arctan" function )....

So   if   tan (x)   = y,  

Then

arctan (y)   =  x

what is 139.675 what? in pounds

There is not answer because you have given no units.

(X-5) (X+4)/ X2 - 3X ≤ 0

3a divided by (6b)

\(3a/(6b) = \frac{3a}{6b}= \frac{a}{2b}\)

That is probably the best answer :)

it is 3a/6b. you could go to 0.5(a/b) but 3a/6b has more meaning.

It is False.

the right answer is:

𝐀𝐩𝐩𝐫𝐨𝐱𝐢𝐦𝐚𝐭𝐞𝐥𝐲 𝟔𝟖% 𝐨𝐟 𝐭𝐡𝐞 𝐝𝐚𝐭𝐚 𝐯𝐚𝐥𝐮𝐞𝐬 𝐥𝐢𝐞 𝐰𝐢𝐭𝐡𝐢𝐧 𝟏 𝐬𝐭𝐚𝐧𝐝𝐚𝐫𝐝 𝐝𝐞𝐯𝐢𝐚𝐭𝐢𝐨𝐧 𝐨𝐟 𝐭𝐡𝐞 𝐦𝐞𝐚𝐧 𝐢𝐧 𝐛𝐨𝐭𝐡 𝐝𝐢𝐫𝐞𝐜𝐭𝐢𝐨𝐧𝐬.

Approximately 95% of the data values lie within 2 standard deviations of the mean in both directions.

Approximately 99.7% of the data values lie within 3 standard deviations of the mean in both directions.

Hope it helped