action

While talking, Li Wei casually wrote a mathematical equation on the blackboard.
"It is known that the ellipse X-square+Y-square=1 and the straight line X-Y+B=0 intersect at two points PQ, and O is the origin of the coordinate. If OP is perpendicular to OQ, find the value of B and write the process."
"The strongest Xueba system is on, and the progress is 99%..."
who? Who is talking? Qin Luo looked around.
system! At this moment, Qin Luo became excited. As an old bookworm of the 21st World, he was very familiar with the system.
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