JEE Main
- Exam
- JEE Main
- Subject
- Mathematics
- Chapter
- Trigonometric Ratios & Identities
JEE Main · Mathematics · Trigonometric Ratios & Identities
12^ ^ ^ - 12^ ^ ^ 12^ ^ ^ + 12^ ^ ^ + 147^ ^ ^ 147^ ^ ^ =
Options
- A-2
- B0
- C-1
- D1
Correct answer
B. 0
Step-by-step solution
\cos 12^{{}^{{}^{\circ}}}-\cos 78^{{}^{{}^{\circ}}}}{\cos 12^{{}^{{}^{\circ}}}+\cos 78^{{}^{{}^{\circ}}}}+\tan 147^{{}^{{}^{\circ}}}=\frac{-2 \sin 45^{{}^{{}^{\circ}}} \sin \left(-33^{{}^{{}^{\circ}}}\right)}{2 \cos 45^{{}^{{}^{\circ}}} \cos 33^{{}^{{}^{\circ}}}}+\tan \left(180^{{}^{{}^{\circ}}}-33^{{}^{{}^{\circ}}}\right)=\tan 45^{{}^{{}^{\circ}}} \tan 33^{{}^{{}^{\circ}}}-\tan 33^{{}^{{}^{\circ}}}=\tan 33^{{}^{{}^{\circ}}}-\tan 33^{{}^{{}^{\circ}}}=0