Tangents from an external point to a circle are equal in length. So, the lengths of PA and PB are equal.
We know that PA=x and PB=x2+1
PA = PB
x=x2+1
x2−x+1=0
Now, this is a quadratic equation.
If we compare to the standard form ax2+bx+c=0,a=1,b=−1 and c=1.
b2−4ac=(−1)2−4(1)(1)=1−4=−3.
Since b2−4ac<0, the equation will have no real roots.
Hence, there are no real values that satisfy the given condition.