trig

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solve for x

6tanx - 4sinx = 1

i tried it but got a quartic formula :S

16sin^4x + 8sin^3x + 37sin^2x - 36 = 0

  • trig -

    This is a "nasty" problem and it does not simplify easily.
    I don't know how you got your quartic equation.

    I rewrote it as 6tanx = 1 + 4sinx
    then graphed f(x) = 6tanx and
    g(x) = 1+ 4sinx

    There are two intersection points, one in quadrant I and another in quadrant III.

    After a few iterations, I got x= 23.27ยบ to come pretty close.

    This is way beyond any highschool level I know, where did you get that question ?

  • trig -

    I got the quartic by moving the sin to the right, squaring both sides, then multiplying everything by sin^2 and then changing the cos to sin.

    My friend gave me this question, and he got it from his virtual school for gr 12 advanced functions lol.

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