Question

please solve this with steps​

Answer 1

hey mate

here is the answer:-

27.

we know that ,

π/20=9°

[π radian=180°]

[1 radian=180°/π]

so,

3*π/20=3*9°=27°

5*π/20=5*9°=45°

7*π/20=7*9°=63°

9*π/20=9*9°=81°

15*π/20=15*9°=135°

thus,

the equation becomes,

tan 9°* tan 27° * tan 45° *tan 63° *tan 81° *tan 135°

[tan a=cot (90°-a)]

=>cot 81°* cot 63°* tan 45°*tan 63° *tan 81° *tan 135°

[tan a*cot a=1]

=>1*tan 45° *tan 135°

=>1*1*-1

=> -1 (Answer)

2) is the correct option..