Application of DerivativeHard
Question
If the line ax + by + c = 0 is a normal to the curve xy = 1, then
Options
A.a > 0,b > 0
B.a > 0,b < 0
C.a < 0,b > 0
D.a < 0,b < 0
Solution
Given, xy = 1 ⇒ 
Thus slope of normal = x2 (which is always positive) and it is given ax + by + c = 0 is normal whose slope = -
⇒
or 
∴ a and b are of opposite sign.
Thus slope of normal = x2 (which is always positive) and it is given ax + by + c = 0 is normal whose slope = -
⇒
or ∴ a and b are of opposite sign.
Create a free account to view solution
View Solution FreeMore Application of Derivative Questions
The rate of change of the area of a circular disc with respect to its circumference when the radius is 3 cm, is-...If g(x) is a curve which is obtained by the reflection of f(x) = by the line y = x then...If a variable tangent to the curve x2y = c3 makes intercepts a, b on x and y axis respectively, then the value of a2b is...The length of subtangent to the curve x2 + xy + y2 = 7 at the point (1, -3) is-...The value of c for the function f(x) = log sin x in the interval is-...