Results 1 to 2 of 2

Math Help - Trig - Finding Angles

  1. #1
    Newbie
    Joined
    Jan 2008
    Posts
    18

    Trig - Finding Angles

    Having trouble with my Trig these days. I was wondering if you could help me out?

    Q. If Angle B is acute and TanB = \frac 3{4}

    Find sinB, cosB, sin2B and tan2B

    - - -

    Also, could anyone help me with another solving for 0 ≤ x ≤ 360 question?

    Q. 4 - sinx = 4cos^2x

    Methods would be great. Thanks! Always appreciative of response
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Senior Member
    Joined
    Dec 2007
    From
    Melbourne
    Posts
    428
    Q. If Angle B is acute and TanB =

    Find sinB, cosB, sin2B and tan2B
    using \tan = \frac{opposite}{adjacent} we can draw a right angle triangle like this:

    Trig - Finding Angles-pythag.jpg

    can you continue?

    For the last 2 you may like to use these:
    \sin(2x) = 2\sin(x)\cos(x)
    \cos(2x) = \cos^2(x)-sin^2(x)
    There are other formulas you might know but these are the ones I have memorised.

    Also, could anyone help me with another solving for 0 ≤ x ≤ 360 question?

    Q.
    The first step uses \sin^2(x)+\cos^2(x)=1
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 12
    Last Post: November 22nd 2011, 06:02 PM
  2. all possible angles of a trig ratio
    Posted in the Trigonometry Forum
    Replies: 5
    Last Post: July 1st 2009, 11:03 AM
  3. Trig Angles
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: April 9th 2009, 01:59 PM
  4. Hexagon Angles/Trig.
    Posted in the Trigonometry Forum
    Replies: 4
    Last Post: February 20th 2009, 06:19 PM
  5. Trig angles
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: January 29th 2009, 09:24 AM

Search Tags


/mathhelpforum @mathhelpforum