Question

3) Consider the sequence -11 ; 2sin3x ; 15; ...

3.1.1) Determine the values of x in the interval [0 ; 90] for whichthe sequence will be arithmetic.​

Answer 1

9514 1404 393

Answer:

  x = 30

Step-by-step explanation:

In an arithmetic sequence, any given term is the average of the two terms that come before and after. The middle term of this sequence must be ...

  2sin(3x) = (-11 +15)/2

  sin(3x) = 1 . . . . . . . . . . simplify and divide by 2

Then the value of 3x must be 90°, so ...

  x = 90/3 = 30

There is one value of x in the interval [0, 90] that makes this sequence arithmetic: x = 30.