buktikan bahwa sin⁴x - cos⁴x = 1-2 cos²x
Matematika
fdeanaufatmand1
Pertanyaan
buktikan bahwa sin⁴x - cos⁴x = 1-2 cos²x
2 Jawaban
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1. Jawaban daffaci
sin4 x - cos4 x = sin2 x sin2 x - cos4 x = (1-cos2 x)(1-cos2 x) - cos4 x = ( 1 - 2 cos2 x + cos4 x - cos4 x = 1 - 2 cos2 x (Terbukti ruas kiri = ruas kanan) -
2. Jawaban susanto17
sin⁴x - cos⁴x = 1-2 cos²x
(sin^2 x + cos^2 x)(sin^2 x - cos^2 x) =1 - 2cos^2 x
(1)[(1-cos^2 x)- cos^2 x] = 1 - 2cos^2 x
1 - 2cos^2 x = 1 - 2cos^2 x
semoga dimengerti dan terima kasih