sin15°cos45°-sin75°sin45°=（）A．12B．-12C．32D．-32

Question

(1)/(2)
B．-(1)/(2)
C．(√(3))/(2)
D．-(√(3))/(2)(1)/(2)1122
(1)/(2)
C．(√(3))/(2)
D．-(√(3))/(2)(1)/(2)1122
(√(3))/(2)
D．-(√(3))/(2)(√(3))/(2)√(3)√(3)√(3)

3

322
(√(3))/(2)(√(3))/(2)√(3)√(3)√(3)

3

322

Answer 1

sin15°cos45°-sin75°sin45°=sin15°cos45°-cos15°sin45°=sin（15°-45°）=sin（-30°）=-(1)/(2)，
故选B． (1)/(2)111222，
故选B．