1. N

    Solve for x+y+z

    if 36/11=3+1/(x+1/(y+1/z)) , where x,y,z are natural number Answer is 6 but i want steps ....
  2. F

    Why this equation is true? Can someone explain?

    Can someone explain why this equation is true? I came up with it some time ago and did not understand why it's true: Is there some specific rule for that? Maxima CAS could not tell if it's true, but it is.(Surprised) \frac{2 \tan{\left( \frac{\alpha }{2}\right) }}{\tan{\left( \alpha \right)...
  3. D

    Partial Differential Equation

    Help please, I need to solve this differential equation x\frac{\partial^2 U}{\partial x^2}+y\frac{\partial^2 U}{\partial y^2}=aU in Matlab (where "a" is a constant parameter, it can be taken by any), I wanted to use the Partial Differential Equation Toolbox, but I ran into a problem, the...
  4. S

    Calculating Gross Totals - Business

    Hello there, to give some context, I'm a business owner who sells concessions like food and drinks. I'm using Excel to help me track my sales and gross. What I'm trying to do is find an equation that will allow me to find my Gross Total from my Sum Price and Sum Count. To give an example...
  5. A

    How to arrange a football team and substitutions

    Hi all, First time on the forum for me, looking for some help on a practical problem! Basically me and some colleagues have a football match tomorrow, and we would like to figure out how we can all spend the same time on the field, given some restrictions: Strikers: Iago, Javier Midfielders...
  6. D

    I don't understand this boolean simplification - basic boolean laws

    I am trying to simplify x’y’z’ + x’yz + xy’z’ + xy’z + xyz from using online calculators, i think the sum of products answer should be y’z’ + yz + xy' but I am only getting as far as here: = x’y’z’ + x’yz + xy’z’ + xy’z + xyz = y’z’(x’ + x) + yz(x’ + x) + xy’z = y’z’ + yz + xy’z...
  7. R


    Hi all, I am posting this at the pre-university section because I think it is not that difficult. It is probably a simple question but I just do not get it. The following text is from a paper: "We primarily measure bank risk using the z-score ofeach bank, which equals the return on assets...
  8. O

    Exponential functions

    Hi, I hope someone can help. I'm currently on 8c and I'm not really sure how to figure out the amount of people in year 2050. I developed an equation which only works with the table that was provided for 8: p(t) = 2^(t x 0.1) x 5 - the only problem is that it seems to not work when I plug in...
  9. B


    How do I put z = x/ (x + y) in terms of x?
  10. B

    How do I find the value of $x$ in this equation.

    The equation is $$\dfrac{1}{a}+b+x=\dfrac{1}{a}+\dfrac{1}{b}+ \dfrac{1}{x} $$ I've tried $$\require{cancel}\dfrac{1+ab+ax}{a}=\dfrac{bx+ax+ab}{abx}\\abx(1+ab+ax)=a(bx+ax+ab)\\\cancel{abx}+a^2b^2x+a^2bx^2=\cancel{abx}+a^2x+a^2b\\a^2b^2x+a^2bx^2=a^2x+a^2b$$ But, don't understand how to solve...
  11. Z

    Possible to find "w" in this equation?

    My equation is: 1. w(x+y+z)= 276.40 2. w(x+1.5y+z)= 327.53 3. w(1.5x+y+z)= 355.06 4. w(3x+2.7y+3z)= 798.54 the 4th equation can be swapped to w(2x+1.5y+z)= 484.83 if needed Is it possible to find "w" from the equation above? Thanks in advance
  12. S

    I need help founding Extrema of a Function

    Hey Guys I hope All is fine ? Please I need Helping getting the points critiques And if it's minimum or maximum Function : f(x;y) = xlny-ylnx Thanks
  13. B

    need help with logarithmic equation solving

    Hi all. I have a question regarding the following equation: 2x +2x+1 2x+2 = 56 (question: solve equation for x) I don't know how to solve this, but I thought I might start to rewrite it like this. And then solve the problem by making use of rules for natural logarithmic functions. log2(x) +...
  14. V

    Finding the equation of a surface of revolution

    Can someone verify if my solution to this problem is correct please? We are given a curve \left ( C \right ) : y=0, (x+3)^{2}+4z^{2}-15=0 and it is asked to find the equation of the surface that is produced if C rotates around the line \left ( l \right ) : y=0, x=-3 Solution: From a...
  15. sakonpure6

    Mass flow rate equation

    Hello, I am working with the mass flow rate equation which is: \frac{d \dot{m}}{dt}=\dot{m}_{in}-\dot{m}_{out} To determine the change of the height of water in a reservoir. Assuming m_in = 10 and m_out = sqrt(20h), then : \frac{d (\rho \cdot Q) }{dt}=\rho \cdot Q_{in} - \rho\cdot Q_{out}...
  16. K

    Trig equation over specified interval

    2sin(x-7) + 6 = cos(2x-10) + 8 Solutions in [6,14] I don't even know where to begin. If there wasn't a constant I would set it to 0 and try sum to product then find zeros. Then there's dealing with the applied interval. Ken T. Also did a rough sketch to make sure it wasn't a trick...
  17. M

    find equation of tangent line to graph at the function given value of x

    f(x)= -2x^(1/2)+x^(3/2), x=4. So I know we need a point, and a slope. f(4)= -2(sqrt4) + (sqrt16) with an index of 3. f(4)= -4+ 2(sqrt2) with an index of 3. so are point is (4, -4+ 2(sqrt2) with an index of 3) now we need to find f'(4) to find the slope which is : limit of x approaching...
  18. S

    Simplifying this equation

    I am trying to simply this equation, and help will be appreciated.
  19. C

    Equation to solve a basic problem

    Hi, Not sure if I'm at the right place but I need an equation if possible. a – c = 44 (variable) a + b + c is always 100 b is always 53% of b + c what is the formula to calculate the values of a, b & c when the 44 changes? Any help would be much appreciated. Thanks.
  20. S


    a sqrt a +b sqrt b = 183 and a sqrt b + b sqrt a = 182 Sent from my GT-I9505 using Tapatalk