BITSAT2020MathematicsApplication of DerivativesActual
The equation of the tangent to the curve y=b e^ -x/a at the point where it crosses the y -axis is
Options
- Ax a - y b =1
- Ba x+b y=1
- Ca x-b y=1
- Dx a + y b =1
Correct answer
D. x a + y b =1
Step-by-step solution
y=b e^ -x / a meets the y -axis at (0, b) . Again, d y d x =b e^ -x / a (- 1 a ) At (0, b), d y d x =b e⁰ (- 1 a )=- b a Therefore, required tangent is y-b=- b a (x-0) or x a + y b =1