All Answers 358187 Answers

This is Physics and EP should answer this one! But here is my two-cents' worth.

When you approach a source of stationary light, or the other way around, when the source of light is moving towards you, its frequency shifts to the blue end of the spectrum. But, the frequency of blue light is not a constant number but ranges between ~6.1 - 6.7 x 10^14 Hz. Since the choices given are so close to each other, I would say that whatever they measure is the frequency of the light source, 4.39 x 10^14 Hz.

Note: Some expert should check this.

We have

C(5,2) (.15)^2(.85)^3  =  .138  = 13.8%

That's the problem XD

There are 2 pi radians in each full rotation

so

32.2 rotations  x 2 pi radians/rotation = 32.2 x 2 x 3.14  = 202.216 R

40/360 x 100% =11.1% ~~~~ Purple

R + O + Y +G + P = 13+4+5+15+16+12 = 65% of 500 people      13% / 65%  = 20 percent chose red

This is the question,

  Cannot tell ANY of those things without some numbers assigned to the groups.... Sorry !

20 famlies were surveyed

1. We can use a  weights to find the average

[ 6(0) + 3(1) + 3(2) + 6(3) + 1(4) + 1(5)] / 20 =

[ 36 ] / 20 =

18/10  =

1.8 pets = average

2.   List the data

0, 0, 0, 0 ,0, 0, 1, 1, 1, 2, 2, 2, 3, 3, 3, 3, 3, 3, 4, 5

The median  is the sum of the 10th and 11th values / 2  =  [ 2 + 2 ] / 2  = 4/2  = 2

OK, ant....!!!

Thank you, CPhill! 

Well....if all but the initial ones die at the end of the hour....then the number that remain at the end of any hour just must be what we started with....call this N

506 minutes = 506/ 60   = 8 + 26/60 =  26 minutes after the top of the hour

So

N + 26 (5) = 137

N + 130 = 137      

N = 7

What process could you use to solve equations of the form (x + a)(x + b) = 0? In this case there are only two factors (values being multiplied) that are being set equal to 0. How would you solve the equation if there were more than two factors? Explain.

What you have here is 

(x + a) * (x + b) = 0

The ONLY way that two things can multiply together to give zero is if ONE or BOTH of them IS ZERO.

so

x+a=0            or                 x+b=0

Now you can 'digest' that properly and then finish the question.

tan (x / 2)  =  csc x - cot x

So...

tan (9pi/8) =

csc (9pi/4) - cot (pi/4)  = 

csc (pi/ 4)   - cot (pi/ 4) =

sqrt (2) - 1

As tertre found   .....!!!

thanks for the info!

Thank you so much!

The left side  is undefined at x = 0  and 2pi ....because csc x is undefined at these values

But cos (0)  and cos (2pi)  = 1

csc pi/ 4 =  sqrt (2)

tan pi/ 4 = 1

cos (pi/4) = 1/sqrt (2)

So

sqrt (2) * 1    not equal to   1/sqrt(2)

csc pi/3 = 2/sqrt (3)

tan pi/3 = sqrt (3)

cos pi/3  = 1/2

So

 [ 2 / sqrt (3) [ * sqrt (3)       not equal to 1/2

This is not true for any value of x

tan(9pi/8)=\(\sqrt{2}-1\) or \(\approx 0.41421356\)

I know it is false i need numbers for a counterexample.

This isn't true

csc x = 1/sin x

tan x =  sin x / cos x

So

csc x tan x  =

(1/sin x) * sin x / cos x    =

1 / cos x   = 

sec x

and  this does not equal  cos x

Masha has a quadratic of the form x^2 + bx + 1, where b is a specific positive number. Using her knowledge of how to complete the square, Masha is able to rewrite this quadratic in the form (x+m)^2 - 63. What is b?

x^2 + bx  + b^2/4    + 1  - b^2/4

(x + b/2)^2 + 1 - b^2/4

And

(x + b/2)^2  -   63

This implies that

+1 - b^2/4  =  -63      rearrange as

64 = b^2/4        multiply both sides by 4

256 = b^2       take the positive root

16 = b       

The HW, Tests, Writing and Participation only sum to 90% of your total grade....what is the other 10% ????

But add all of those percentags up to see what my grade will be for Finals. Ex.

82.1 %

52.05 %

74.2 %

87.03 %

647 / 788 = 82.1 %

23 / 31   = 74.2 %

would this make sense 

Y= 3(x - 4)^3- 3

I shall not cite where I get my stuff