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11 votes
11 votes
19. Solve for the angle x.
sin²(2x) = 1

19. Solve for the angle x. sin²(2x) = 1-example-1
User Lenicliu
by
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1 Answer

25 votes
25 votes

Answer: Е

Explanation:

▪︎ a^2 - b^2 = (a-b)(a+b)

sin^2(2x) = 1

sin^2(2x) - 1 = 0

(sin2x - 1)(sin2x + 1) = 0

sin2x - 1 = 0 or sin2x + 1 = 0

sin2x - 1 = 0

sin2x = 1

2x = 90° + 360°n

x = 45° + 180°n

▪︎180° means half of the unit circle, therefore,

x = 45° + 360°n and

x = 45° + 180° + 360°n = 225° + 360°n

sin2x + 1 = 0

sin2x = -1

2x = 270° + 360°n

x = 135° + 180°n

therefore,

x = 135° + 360°n and

x = 135° + 180° + 360°n = 315° + 360°n

n is an integer

19. Solve for the angle x. sin²(2x) = 1-example-1
User Mattpx
by
3.3k points