The correct answer is Option 2 i.e. 3
Concept Used:
sin(90 - A) = cosA
tan(90 - A) = cotA
sec(90 - A) = cosecA
Explanation:
According to the given question,
tan15°tan35°tan60°tan55°tan75°sin33°cos57°+sec62°sin28°+cos33°sin57°+cosec62°cos28°
⇒ tan15°tan(90−55°)tan60°tan55°tan(90−15°)sin(90−57°)cos57°+sec62°sin(90−62°)+cos(90−57°)sin57°+cosec(90−28°)cos28°
⇒ tan15°cot55°tan60°tan55°cot15°cos57°cos57°+sec62°cos62°+sin57°sin57°+sec28°cos28°
⇒ tan60°cos257°+1+sin257°+1
⇒ 33 = 3
Hence the required answer is 3.