JEE Main 2024 Mathematics question
If the area of region {(x, y) : , 1 ≤ x ≤ 2, 0 < a < 1} is (log2) − then the value of 7a − 3 is equal to:
Answer: (C)
Solution
Area = ∫₁²(1/x − a/x²)dx = ln 2 − a/2 = ln 2 − 1/7, so a = 2/7 and 7a − 3 = −1.
If the area of region {(x, y) : , 1 ≤ x ≤ 2, 0 < a < 1} is (log2) − then the value of 7a − 3 is equal to:
Area = ∫₁²(1/x − a/x²)dx = ln 2 − a/2 = ln 2 − 1/7, so a = 2/7 and 7a − 3 = −1.