Given equation: 2Py2−8y+P=0
On comparing by the general equation
ax2+bx+c=0
We get, a=2P,b=−8,c=P
If the equation has equal roots, then
b2−4ac=0
⇒(−8)2−4×2P×P=0
⇒64−8P2=0
⇒8P2=0
⇒P2=648
⇒P2=8
⇒P=±2√2,
Thus for the value P=±2√2, the equation 2Py2−8y+P=0 has equal roots.