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  1. N

    Some Trig Questions

    If you guys could help me solve these, I'd greatly appreciate it. 1. Simplify 2cos^23x-1 (answer is cos6x) 2. Prove \frac{sin2\Theta +1}{cos2\Theta }=\frac{cos\Theta -sin\Theta }{cos\Theta +sin\Theta } 3. Prove...
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    Curve Sketching

    Hi. I have a quick question. I know how to sketch something like y=sin2x and y=sin(x+pi) But what would I do about y=sin(2x+pi) Do I do the same as y=sin2(x+pi)? Or is it something else?
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    3D Trig Help

    137m (to the nearest metre)
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    3D Trig Help

    A tower stands at the foot of a plane which is inclined to the horizontal at an angle of 12 degrees. A line 100m is measured straight up the incline from the foot of the tower. It is found that at then end of this line the tower subtends at an angle of 62 degrees. Calculate the height of the...
  5. N

    Quick Question

    I'm having a brain freeze here. Could someone help me prove this equation \frac{sin\Theta }{1+cos\Theta }=\frac{1-cos\Theta }{sin\Theta }
  6. N

    Quick Question

    I know this is really simple, but I don't think I have learnt it. How would you evaluae sin^2 30? Is is sin900? or 0.5 x 0.5
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    Trig Identity Help

    For question 3, the answer says it's a sec\Theta cosec\Theta but I get asin^2\Theta
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    Trig Identity Help

    Hi. I need some assistance on the following equations Simplify: 1.(sec^2\Theta -1)tan(90 \degree -\Theta ) 2.1-sin^2(180+\Theta ) 3.\frac{x^2}{\sqrt{x^2-a^2}} \;\;\;when x=asec\Theta 4.\sqrt{a^2-x^2}\;\;\;\; when x=acos\Theta
  9. N

    Simple Trig

    Yes you are right. Can someone put up a diagram because I can't get the what the actual question is saying.
  10. N

    Simple Trig

    Can someone help me because I just can't seem to get this. A wooden stake, S, is 13m from a point, A, on a straight fence. SA makes an angle of 20degrees with the fence. If a goat is tethered to S by a 10m rope, where, on the fence, is the nearest point to A at which it can graze.
  11. N

    Compounds in Coal

    Can anyone give me a list or a site of the range of compounds in coal.
  12. N

    Cubic Roots Question

    Can someone explain this question further for me.
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    Cubic Roots Question

    Can someone else confirm this?
  14. N

    Cubic Roots Question

    The answer says 3x^3 - 4x^2 +24 = 0
  15. N

    Cubic Roots Question

    Hi. I have been stuck on this question for literally the past few days. Find the cubic equation whose roots are twice those of the equation 3x^3-2x^2+1=0
  16. N

    Quick polynomial question

    Oh. I mean when you graph it, how do you determine which way the ends point?
  17. N

    Quick polynomial question

    I'm just wondering. What's the best way to determine whether a polynomial in its factor form is positive or negative. eg. (3-2x)(1-x)^4(x+3)
  18. N

    Need help with a question on functions

    Well a function is defined as an equation with 1 y-value for each x-value. In this case, if the equation was y=2x-1, then yes it would be a function. However, this equation is a region, meaning that there would be more than 1 y-value for each x-value. First thing you do is you draw the graph...
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    What textbook is this?

    You guys think it is worth buying some of the modules? Like how good is it?
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    What textbook is this?

    In class, we got a whole bunch of notes and I was wondering what textbook it comes from. There is information, followed by questions under "For You To Do." There are also answers in the textbook. Some sub-headings include 4. Ionisation Energy 24. The Mole and Chemical Equations 25. Empirical...
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