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I didn't look much into it, so i simply missed it ;)

I edited the answer now. :D

I use the calculator a lot at the time, it's great and easy to use :D

That is really good thinking ChoZerr.

Why didn't you include x=-1.5 as a second answer ?

How did you make a graph?  I guess you made y=2x2+5x+3     ??

But did you do it by hand and graph a set of points?

or did you use a graphing calc?  

or did you do it another way?

Yes, it makes me happy every time :D

Thanks Alan :))

I made the graph, and the only places to hit 0 was -1 and -1,5

That is one "Happy Dog" you have there.

I think it is a great icon   

1.  If vector B is has magnitude 140km and is 65° above the positive x axis then -B will have the same magnitude but will be 65° below the negative x axis (assuming the vector starts at (0, 0).  i.e. both the x and y coordinates will be reversed.

2.  65° East of North is 25° above the positive x-axis!

Welcome to the forum ChoZerr  

How did you get you answer ?     Was it by trial and error perhaps ??   

x=-1 or -1,5

Thurs 5/11/15

1) Forum problems and a wonderful show of appreciation.  Thanks Juriemagic

    http://web2.0calc.com/questions/hi-melody_1#r4

2)    Birthday trick with numbers.            Thanks guest and Heureka

       http://web2.0calc.com/questions/take-the-day-number-of-your-birthday-eg-if-your-birthday-is-28-april-take-28-multiply-your-number-by-4-add-14-multiply-the-result-by-25-subtract-230/new#edit

3)   Thanks Chris but I like our guests answer :)   

       http://web2.0calc.com/questions/volume-of-spheres#r1

4)   Why can't I take (-1)^1/2                    Melody

      http://web2.0calc.com/questions/1-1-2-error

5)  Minimize the price.     Fabulous answer from CPhill

     http://web2.0calc.com/questions/linear-programing#r3

6)  interesting simplification        Melody and Heureka

     http://web2.0calc.com/questions/how-do-i-solve-this-equation

7) Force work power and time.     Thanks Will85237   (and welcome back to the forum too) 

    http://web2.0calc.com/questions/heeeeeelp-got-test-tomorrow#r3

8)   Solving a polynomial of degree 4 equation.    Melody and Heureka

      http://web2.0calc.com/questions/solve-polynomial

9) Newton's method to find minimum.    Thanks Alan

     http://web2.0calc.com/questions/use-newton-s-method-to-find-the-absolute-maximum-value-of-the-function-f-x-2x-sin-x-0-x-correct-to-six-decimal-places#r1

or 0,6 depending if it's n^5 or n5

1.245731

Not 32   because (-2)^5 = -32      

but

(-2)^6=64       

The temperature change in a chemistry experiment was -2C every 30 min. The initial temperature was +6C. What was the temperature after 4 h

4 hours = 8 half hours

0, 1, 2, 3, 4,    5,  6,  7,  8   half hours

6, 4, 2, 0, -2, -4, -6, -8,  -10

-10 degrees C    

@@ What is Happening?  [Wrap4]    Wed 4/11/15   Sydney, Australia Time 6:35pm   ♪ ♫

Hi everyone,

A very big thank you to our answerers,  Saseflower, CPhill, Heureka, Gilbertx5 and Will8537.   

There was no where near enough time to answer all questions or check all answers today, this happens quite often.

REMEMBER: Priority goes to members.  I believe credit has been given to all member answerers and that all member questions have been answered by someone.  If yours has not been answered perhaps it is because it does not make sense or more likely for higher level question, no-one with the knowledge to answer was on today.  

Interest Posts:

If you ask or answer an interesting question, you can private message the address to me (with copy and paste) and I will include it.  Of course only members are able to do this.  I quite likely will not see it if you do not show me.  

1)   What to order?      I found this really confusing.        Melody

Your question does not make any sense.

What number does 3, 15, 5, and 9 go into evenly?

Well 3 and 5 go into 15 so you only need to worry about what 15 and 9 both go into.

 15  =  3*5

 9  = 3 *3 

so 3*3*5 = 45 will be you answer

All multiples of 45 will work just fine  :)

That sounds right to me but I don't know about vectors.

Can someone knowledgable take a lquick look at this query please.  :))

determine the value of k for which this equation has two real roots: kx^2+6x+5=0

\(x = {-b \pm \sqrt{b^2-4ac} \over 2a}\\\\ D = b^2-4ac\)

discriminant  D > 0 ( two real roots )

a = k

b = 6

c = 5

D = 6*6 - 4*k*5

D = 36 -20k

D > 0 ( two real roots ):

\(\begin{array}{rcll} 36 - 20k &>& 0 \qquad &| \qquad -36\\ -20k &>& -36 \qquad &| \qquad \cdot(-1)\\ 20k &<& 36 \qquad &| \qquad :20\\ k &<& \frac{36}{20} \\ k &<& \frac{9}{5} \\ \mathbf{k} &\mathbf{<}& \mathbf{1.8} \\ \end{array}\)

I am not comfortable with your wording but if you mean what I think you mean than 

r = sqrt(64+1)=sqrt(65)

Tan theta =8

And

Sin theta = -8/sqrt(65)

69 nah jk it 36

Wed 4/11/15

1)   What to order?      I found this really confusing.        Melody

     http://web2.0calc.com/questions/linear-programing#r1

2) This is a simple vector question.  Could someone knowledgable take a quick look please.

    http://web2.0calc.com/questions/vectors-in-physics

S=-13

2x - 3y = 7

Plug in x

2(10) - 3y = 7

Simplify

20 - 3y = 7

Subtract 20 from both sides

-3y = -13

Divide -3 on both sides

y = 3/13

or

y = -4.3333333333333333

(I would do the fraction)

Hopefully this is what you were asking, I'm not entirely sure though :)