English
Hindi
10-2. Parabola, Ellipse, Hyperbola
easy

${\text{c}}$ ના જે મુલ્ય માટે $y\, = \,\,\,4x\,\, + \;\,c$ એ વક્ર $\frac{{{x^2}}}{4}\,\, + \;\,{y^2}\, = \,\,1\,\,$ ને સ્પર્શે તો મુલ્યોની સંખ્યા........ 

A

$0$

B

$1$

C

$2$

D

અનંત

Solution

We know that the line $y=m x+c$ touches the curve $\frac{x^2}{a^2}+\frac{y^2}{b^2}=1$ if $c^2=a^2 m^2+b^2$

Here $a^2=4, b^2=1, m=4$

$c^2=64+1 \Rightarrow c=\pm \sqrt{65}$

$c =+\sqrt{65} \text { and }-\sqrt{65}$

$\therefore c$ has $2$ values

Standard 11
Mathematics

Similar Questions

Start a Free Trial Now

Confusing about what to choose? Our team will schedule a demo shortly.