Question

Find the exact value of each expression. sin75° cos(-75°)

Answer 1

Answer:

Step-by-step explanation:

sin 75°

sin(30°+45°)

sin30°*cos45°+cos30°sin45°

1/2*1/$\sqrt{2}$ + $\sqrt{3}$/2*1$\sqrt{2$

1/2$\sqrt{2}$+$\sqrt{3}$/2$\sqrt{2}$

1+3/2$\sqrt{2}$

cos(-75°)

-cos(180°-105°)

-cos(-105°)

cos 105°

cos(45°+60°)

cos45°cos60°-sin45°sin60°

1/$\sqrt{2}$ *1/2-1/$\sqrt{2}$ *$\sqrt{3}$ /2

1/2$\sqrt{2$-$\sqrt{3$/2$\sqrt{2}$

1-$\sqrt{3}$/2$\sqrt{2}$

Answer 2

sin(75)

=0.96

cos(-75)

=0.25