Posts by Qun

Total # Posts: 21

  1. MATH

    Yes, it is right.
  2. maths

    You need to isolate P from the rest. Basically you do opposite operations to isolate a variable. In this case, subtract 5/3 on both sides: then P = q - 5/3
  3. Algebra II

    Here is the answer: Let S represent the sum of the expression then: S = 1/5 + 1/5^2 +... + 1/5^n ---- (a) multiply both sides by 1/5 (1/5)S = 1/5^2 + 1/5^3 +.. + 1/5^n + 1/5^(n+1) ---- (b) use equation (a) subtract equation (b) (4/5)S = 1/5 - 1/5^(n+1) multiply 5 on both sides...
  4. Calculus: drwls, please

    Hi, You need to draw f(x) =1/x first and then transform it to f(x) = (1/x) - 4 To draw f(x) = 1/x, all you need to do is find several points, example: let x=1, then f(1)=1, you get one point (1,1) let x = 0.5, f(0.5)=1/0.5=2, another point (0.5,2). Try to get 5-10 points and ...
  5. Advanced Math

    Yes it is suppose to be f(n) = n^2 + 4n is O(n^2) : Hi, I assume n>1. let g(n)=n^2 This is straight forward according to big O notation. f(n) = n^2 + 4n <= n^2 + 4n^2 = 5n^2 That means |f(n)|<=C|g(n)| where C is a constant. According to big O definition f(n) is O(n^2)
  6. Math

    a math expression has meaning in it, it is not just a bunch of operations. The older of operations is a set of rule that everybody will follow so that we have a solid foundation to communicate with each other so that the meaning in an expression can be delivered without ...
  7. MATH

    Linear model mean the rate of change is constant. SO the rate is (4.4-24.3)/45 = 0.442 a) So the model function is f(t)=24.3 -0.442t b)in year 1975, t=30 f(30)=24.3-0.442*30 = 11.04 about 11 million. c) in year 1980, t=35 f(35)=24.3-0.442*35 = 8.83 million
  8. geometry

    hint: how are diameter and circumference related? How are radius and diameter related?
  9. math

  10. math 116

    This is the reason, using 1/2 + 1/3 as example: the denominator means the number of equal parts you divide the whole thing into. 1/2 means you divide the whole thing into 2 equal parts and you take one part. 1/3 means you divide the same whole thing into 3 equal parts and you ...
  11. math

    The standard notation for the length of medians: a=(1/2)*sqrt(2C^2+2B^2-A^2) b=(1/2)*sqrt(2C^2+2A^2-B^2) c=(1/2)*sqrt(2A^2+2B^2-C^2) square both sides: a^2=(1/4)*(2C^2+2B^2-A^2) b^2=(1/4)*(2C^2+2A^2-B^2) c^2=(1/4)*(2A^2+2B^2-C^2) multiply 4 on both sides: 4a^2=(2C^2+2B^2-A^2) ...
  12. math

    this line goes through origin. So the y-intercept is 0
  13. math

    Find the distance formula in the textbook and plug in numbers.
  14. Math(Easy Survey Please Help)

    1. Do you exercise or work out on a regular basis? no 2. Are you male or female? male 3. Do you smoke? no 4. How many carbonated soft drinks do you consume in a week. none 5. Do you drink coffee. occasionally 6. How many servings of fruit, or fruit juice do you consume in a ...
  15. Math

    Your problem is a wrong one. tenth is the first decimal digit.
  16. Math

    This is rather about the concept: 1) Identity means both sides are equal no matter what the value x will take. example: 2+x=x+2 2) inconsistent: means the equation is not true regardless the x value. example: 2+x=3+x 3) conditional: The equation is true at certain x value. ...
  17. math

    1) divide both sides by 25, we get x^2=13/25 take square root x = +/- sqrt(13/25) sqrt means square root. example: sqrt(5) means square root of 5. 2) The same kind of problem: divide by 2 on both sides: (x-5)^2 = 3/2 take square root: x-5 = +/- sqrt(3/2) add 5 on both sides: ...
  18. Algebra

    Let Total be x 1) Pink (1/2)x remain (1/2)x 2) pink (3/4)*(1/2)x remain (1/4)(1/2)*x 3) Orange (1/2)(1/4)(1/2)x remain: (1/2)(1/4)(1/2)x So the red is (1/2)(1/4)(1/2)x Which is one-16th of the whole thing, which is 16.7% Contact me for quick homework help.
  19. Trigonometry

    replace 150(in the parenthesis) by 180 in my last post, that was a typo.
  20. Trigonometry

    Tim, This can be done very easily by BASICS of Tangent function: Tan has a period of PI, which is 180 degree. When you have a angle like 225, all you need to do is add or subtract multiples of 180(in this case, 150 itself) to get a common angle: 225-180 = 45 Tan(45)=1, since ...
  21. geometry

    surface area = 2x^2 + 4xh where x is the length of the side and h is the height. let x= 1/3h Then 224 = (2/9)h^2 + (4/3)h^2 solve it h = 12 then x = 1/3 h = 4 So the length is 4 and height is 12