cos100°cos70°+sin100°sin70°

jwb

cos 100 cos 70 + sin 100 sin 70  = cos (100-70)
= cos 30
= 1/2 √3

cos100°cos70° + sin100°sin70°
cos (100-70)
cos 30°
√3/2

#maaf jika salah semoga membantu