SOLUTION: The smallest positive number for which 3sin(2x−6)=1 Hint: Proceed as in the preceding problem to find some solution of the equation. Then look for the smallest positive.

Algebra ->  Logarithm Solvers, Trainers and Word Problems -> SOLUTION: The smallest positive number for which 3sin(2x−6)=1 Hint: Proceed as in the preceding problem to find some solution of the equation. Then look for the smallest positive.      Log On


   



Question 1188985: The smallest positive number for which
3sin(2x−6)=1
Hint: Proceed as in the preceding problem to find some solution of the equation. Then look for the smallest positive.

Answer by ikleyn(52908) About Me  (Show Source):
You can put this solution on YOUR website!
.
3sin(2x−6)−1=0
~~~~~~~~~~~~~~~~~~~~

We transform given equation this way

    sin(2x-6) = 1/3


After that, we get two possible forms

         (a)  2x-6 = arcsin(1/3) + 2k*pi

    and

         (b)  2x-6 = pi - arcsin(1/3) + 2k*pi


It gives two expressions for x

         (a)  x = (arcsin(1/3) + 6)/2 + k*pi
        
    and

         (b)  x = (pi - arcsin(1/3) +6)/2 + k*pi


Giving values  k= 0 and -1 for(a)  and  k=0 and -1 for (b), we get 4 values for x in the interval [0,2pi), in radians


    1)  x = %286%2Barcsin%281%2F3%29%29%2F2 = %286%2B0.3398%29%2F2 = 3.169918455,


    2)  x = %286%2Barcsin%281%2F3%29%29%2F2 - pi = %286%2B0.3398%29%2F2 - 3.14159 = 0.028328455,


    3)  x = %286+%2B+pi-arcsin%281%2F3%29%29%2F2 = %286%2B3.14159-0.3398%29%2F2 = 4.400876545,


    4)  %286+%2B+pi-arcsin%281%2F3%29%29%2F2 - pi = %286%2B3.14159-0.3398%29%2F2 -  3.14159 = 1.259286545.


The minimum of these 4 values is  0.028328455.     ANSWER

Solved.