Question
If tan 15° = 2 –√3, what is the value of tan 15º
cot 75°+ tan 75º cot 15°.Solution
tan 15° × cot 75° + tan 75° × cot 15° = tan 15° × tan (90° - 15°) + cot (90° -75°) × cot 15° = tan 15° × tan 15° + cot 15° × cot 15° = (tan15°)2 + (cot 15°)2 Now, given tan 15° = 2 - √3 And cot 15° = 1/tan15° = 1/ (2 - √3) = 2 + √3 [on rationalizing] Thus, tan 15° × cot 75° + tan 75° × cot 15° = (tan15°)2 + (cot 15°)2 = (2 - √3)2 + (2 + √3)2 = 7 – 4√3 + 7 + 4√3 = 7 + 7 = 14
- It was Thursday on February 8, 2024, then, what will be the day on February 8, 2028?
It will be Saturday on November 12, 2022. What will be the day on November 12, 2028?
- What is the angle between the hour hand and the minute hand at 7:45 AM?
At what time between 3:30 and 4 will hands of a clock be at the right angles?
It was Tuesday on February 8, 2022. What will be the day on February 8, 2027?
- What is the angle between the hour hand and the minute hand at 3:30 AM?
Day before yesterday is Ranjan’s birthday. On the same day next week falls ‘Christmas’. Today is Saturday, what will be the day after Christmas�...
- The year next to 2014 will have the same calendar as that of the year _________.
Mishti's birthday is on Thursday 27th April. On what day of the week will be Aradhya's Birthday in the same year, if Aradhya was born on 20
- It was Monday on November 12, 2018. What will be the day on November 12, 2028?
Relevant for Exams:
