Had My Pre RMO Test Today !!
Well I had It very Good but did some silly mistakes. But I think i will probably clear the cut off of 50/100. There were 8 question in the paper and I attempted 7. The only Question that i didnt attempt is here:
Q- ABCDE is a regular pentagon. A circle is drawn which is tangent to CD at D and AB at A. F is the mid point of arc AD. So you have to prove that AFDE is a rhombus.
hey dis one was quite easy if u could juz undrstand da fact dat point E & F will b on da opposite side of da centre of da given circle!
ReplyDeletethn on u cn prove dat the angle subtended by AD at da centre is 108* so dat da angle AFD is (pi-half of angle subtended at centre) hence u get da opposite angles as equal...u cn get anothr comdition of adjacent equal sides!
& anothr condition dat the segment AD is bisected by EF!
HENCE PROVED to b a rhombus!!
Well Was bluffed by the angle at the time.. Well it was easy by symmetry also.. I was thinking to do that.. but thought it to be a fluke.. :D
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