Selesaikan sin 3x + cos 2x = 0

sin 3x + cos 2x = 0

Mari kita sederhanakan,

sin 3x + cos 2x = 0

cos 2x = – sin 3x

cos 2x = – cos (π/2 – 3x) [karena, sin A = cos (π/2 – A)]

cos 2x = cos (π – (π/2 – 3x)) [karena, -cos A = cos (π – A)]

cos 2x = cos (π/2 + 3x)

2x = 2nπ ± (π/2 + 3x)

Jadi,

2x = 2nπ + (π/2 + 3x) [atau] 2x = 2nπ – (π/2 + 3x)

x = -π/2 – 2nπ [atau] 5x = 2nπ – /2

x = -π/2 (1 + 4n) [atau] x = /10 (4n – 1)

x = – /2 (4n + 1) [atau] /10 (4n – 1)

solusi umumnya adalah

x = – /2 (4n + 1) [atau] /10 (4n – 1)

x = /2 (4n – 1) [atau] /10 (4n – 1), di mana n Z.

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