Search results

  1. T

    Please help?

    a) dy/dx =2x-5. Sub in x=2 into dy/dx to find gradient. Then use the y-y1=m(x-x1) to find tangent. The normal is the same but the gradient is the negative inverse of the tangent. Since the gradient is different then you have to use the new gradient in y-y1=m(x-x1) to find equation of normal b)...
  2. T

    Differentiation questions

    Im pretty sure when it says that x=2 is a zero, it means that its an intercept, such that when x=2, y=0.
  3. T

    Differentiation questions

    Ah mb, didn't read that the parabola was a tangent to the x-axis
  4. T

    Differentiation questions

    How can you be sure that the gradient at the x-axis is always 0? Like if it cuts the x axis twice, then wouldn't it have a non-zero gradient?
  5. T

    Moderator application form

    likelihood of a non-hsc graduate being mod?
  6. T

    St Marys Into Girraween

    Posted this thread some time ago, but anyways St Mary's is good, but it favours self-learning. They do give you a lot of resources and you can just study of it and if you need help you, the teachers are always there to help you. It wasn't really that much of a change since I was a bit ahead in...
  7. T

    [Inverse Trig] Why does the solution only take into consideration 1 case?

    Yeh tan inverse is from pi/2 to -pi/2 cos inverse is from 0 to pi sin inverse is from pi/2 to -pi/2
  8. T

    [Inverse Trig] Why does the solution only take into consideration 1 case?

    The range of sin inverse is from pi/2 to -pi/2 so that would be in the first and 4rth quadrant. cos inverse range is from 0 to pi so 1st or 2nd quadrant, but since the cos is positive should be in 1st quadrant. Is this what you were asking?
  9. T

    WHAT IS BEST WAY TO LEARN

    why not all
  10. T

    math help

    Once you used difference of two squares, use sum to product formula, then multiply them so that you can use double-angleformula to get rid of the theta/2
  11. T

    math help

    hopefully it's not too blurry,
  12. T

    combs maths help

    AHAHA unluggy
  13. T

    combs maths help

    Cause they are repeating. If you had MMM theres only one way since they are considered the same. If that makes sense
  14. T

    combs maths help

    Combinations is similar to permutations, just that the order matters. Permuation is when the order doesnt matter, and combination is when the order does matter. Combinations are in the form nCr, which is \frac{n!}{r!(n-r)!}. The 4C4 means that from 4 choose 4, and 4C3 means from 4 choose 3 and...
  15. T

    combs maths help

    Case 1: One M's - choose the other 4 letters from AOTH: 4C4 = 1 Case 2: Two M's - choose the other 3 letters from AOTH: 4C3 = 4 Case 3: Three M's - choose the other 2 letters from AOTH: 4C2 = 6 Total = 4+6+1 = 11
  16. T

    combs maths help

    So out of 5 letters to choose out of 7 total letters : _ _ _ _ _. Number of ways to do that is 7P5, which should = to 2520. However hte word MAMMOTH has the letter M repeating 3 times, so you would divide by 3!. Thus the answer should be (I think) 2520/3!. Check with the answers cos im not 100% sure
  17. T

    The Anime Thread

    I mean... Whats everyone watching rn? Tower of god is sick rn for me
  18. T

    Calculus

    Lmao its g dw
  19. T

    Calculus

    For questions like this, its best to actually graph if it since it becomes easier once you visually know whats going on. To do part b, you need to find the equation of the tangents P and Q. So just sub the x and y values into y -y1 = m(x-x1) and you would get the equations. Then since the...
  20. T

    Chemistry: Percentage Composition by Mass

    Yeah nah, I coulnd't seem to find the answer to that. Might have to ask your teacher or jazz, sorry!
Top