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You are not logged in. #1 20060415 01:20:08
circleI have done part a) of the question which need checking & need help on part b) #2 20060417 06:41:19
Re: circleIf you rearrange the equation into you can see what you're doing a bit more, and just pick the coordinates of the centre and the size of the radius straight off. You were right with the answers though. I'm not totally sure what you mean in part (b). Surely there could be any number of possible tangents to the circle? If you're asking for the points at which the xaxis intersects the circle, then this can be calculated by solving the simultaneous equation: So all you need to do is substitute the value of y into the equation for the circle: Therefore the circle intersects the xaxis at points (√5 + 1,0) and (√5 + 1,0). I think. Student: "What's a corollary?" Lecturer: "What's a corollary? It's like when a theorem has a child. And names it corollary." 