Question:

Solve 2 sin x+ 3 cos x=0?

by  |  earlier

0 LIKES UnLike

Solve 2 sin x+ 3 cos x=0?

 Tags:

   Report

5 ANSWERS


  1. 2sinx=-3cosx   sinx/cosx=-3/2   tanx=-1.5  x=taninverse-1.5

       x=-56.31


  2. I love tangent I actually love trig more than I do geometry but can't help you with this one that was like wat 2 years ago for me and prob not even that

  3. 2 sin x + 3 cos x = k cos ( x - α ) for k > 0

    2 sin x + 3 cos x = ( k cos α) cos x + (k sin α) sin x

    2 = k sin α

    3 = k cos α--------α in 1st quadrant

    tan α = 2/3

    α = 0.369 radians

    4 + 9 = k ² ( sin ² α + cos ² α )

    13 = k ²

    k = √13

    √13 cos (x - 0.369) = 0

    x - 0.369 = π/2 , 3π / 2

    x = 1.94 , x = 5.08 (for 0 ≤ x ≤ 2π)

  4. Dont forget all of the other solutions:

    2sin(x) + 3cos(x) = 0

    2sin(x) = -3cos(x)

    sin(x)/cos(x) = -3/2

    tan(x) = -3/2

    x = arctan(-3/2)

    Now tan is negative in the 2nd and 4th quadrants so there are answers there

    x = -56.3deg (1dp) is the solution in the fourth quadrant

    so x = 180n - 56.3 is ALL solutions  

  5. 2 sin x+ 3 cos x=0

    2sinx=-3cosx

    2(sinx/cosx)=-3

    tanx=-3/2

    x=(invtan(3/2))

Question Stats

Latest activity: earlier.
This question has 5 answers.

BECOME A GUIDE

Share your knowledge and help people by answering questions.