NIMCET 2020 — Mathematics PYQ
NIMCET | Mathematics | 2020The tangent to an ellipse x2+16y2=16 and making angle 60° with x-axis is:
Choose the correct answer:
- A.
x−3y+7=0
- B.
x+3y−7=0
3x−y+7=0
Explanation
Solution
1. Standard Form of Ellipse:
Divide the equation by 16:
16x2+1616y2=1616
\frac{x^2}{16} + \frac{y^2}{1) = 1
Comparing with a2x2+b2y2=1:
-
a2=16
-
b2=1
2. Finding the Slope (m):
The tangent makes an angle θ=60∘ with the x-axis.
m=tan(60∘)=3
3. Equation of Tangent:
The equation of a tangent to an ellipse with slope m is:
y=mx±a2m2+b2
4. Substituting the values:
y=3x±16(3)2+1
y=3x±16(3)+1
y=3x±48+1
y=3x±49
y=3x±7
Final Answer:
The equations of the tangents are:
3x−y±7=0
Explanation
Solution
1. Standard Form of Ellipse:
Divide the equation by 16:
16x2+1616y2=1616
\frac{x^2}{16} + \frac{y^2}{1) = 1
Comparing with a2x2+b2y2=1:
-
a2=16
-
b2=1
2. Finding the Slope (m):
The tangent makes an angle θ=60∘ with the x-axis.
m=tan(60∘)=3
3. Equation of Tangent:
The equation of a tangent to an ellipse with slope m is:
y=mx±a2m2+b2
4. Substituting the values:
y=3x±16(3)2+1
y=3x±16(3)+1
y=3x±48+1
y=3x±49
y=3x±7
Final Answer:
The equations of the tangents are:
3x−y±7=0

