Home › UP Board Class 10 › Mathematics › From an external point $P$, tangents $PT_1$ and …
From an external point $P$, tangents $PT_1$ and $PT_2$ are drawn to a circle. Which relation is always true? 
A$PT_1 > PT_2$
B$PT_1 < PT_2$
C$PT_1 = PT_2$
D$PT_1 + PT_2$ equals the diameter
Answer & Solution
Correct answer: C. $PT_1 = PT_2$
The lengths of tangents drawn from an external point to a circle are equal. So if $PT_1$ and $PT_2$ are tangents from the same external point $P$, then $PT_1 = PT_2$.
Related questions
What is the derivative of $x^x$ for $x>0$?If $y=x^{\tan^{-1}x}$, then $\dfrac{dy}{dx}$ equalsThe derivative of $ in^{-1}x$ isThe derivative of $\cos^{-1}x$ isWhat is $\dfrac{d}{dx}(\tan^{-1}x)$?If $y=\dfrac{1}{x^n}$, then $\dfrac{dy}{dx}$ isWhich identity is correct?For the expression $ qrt{1-x^2}$, a useful trigonometric substitution is