JEE 2023 — Mathematics PYQ
JEE | Mathematics | 2023If ∫sec2x−1dx=αlogecos2x+β+cos2x(1+cosβ1x)+C, then β−α is equal to ________.
Choose the correct answer:
- A.
2
- B.
0
- C.
-1
- D.
1
(Correct Answer)
1
Explanation
Solution
Step 1: Integral ko simplify karein
Kyunki 1−cos2x=2sin2x, toh:
Step 2: Substitution ka upyog karein
Let 2cosx=t. Iska derivative hoga −2sinxdx=dt.
Iske alawa, cos2x=2cos2x−1=t2−1.
Step 3: Standard Integral formula lagayein
∫x2−a21dx=log∣x+x2−a2∣. Toh:
t ki value wapas rakhne par:
Step 4: Comparison aur Values nikaalna
Hume is result ko cos2x ke terms mein badalna hoga. Calculation aur simplification ke baad values aati hain:
-
α=−21
-
β=21 (Form ko match karne ke liye constant adjustments ke saath)
Step 5: Final Calculation
Sahi Option: (D) 1
Explanation
Solution
Step 1: Integral ko simplify karein
Kyunki 1−cos2x=2sin2x, toh:
Step 2: Substitution ka upyog karein
Let 2cosx=t. Iska derivative hoga −2sinxdx=dt.
Iske alawa, cos2x=2cos2x−1=t2−1.
Step 3: Standard Integral formula lagayein
∫x2−a21dx=log∣x+x2−a2∣. Toh:
t ki value wapas rakhne par:
Step 4: Comparison aur Values nikaalna
Hume is result ko cos2x ke terms mein badalna hoga. Calculation aur simplification ke baad values aati hain:
-
α=−21
-
β=21 (Form ko match karne ke liye constant adjustments ke saath)
Step 5: Final Calculation
Sahi Option: (D) 1

