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find the value of x for which the points (x, -1),(2,1)and(4,5) are collinear
Two circles cut at A and B. The tangent to the first at A meets the secondsecond at C, and the tangent at B meets the first again at D. Prove that AD and BC are parallel.
If (1+3+5......to nth term)/(2+4+6.......to nth term) =0.95, find n ?