For `2lt=r`

nCr + 2.nC (r-1) + nC (r-2) = (n + 2) Cr (2 <= r <= n)

Consider the family of circles x^2 + y^2= r^2 2 lt r lt 5 . If in the first quadrant, the common tangent to a circle of this family and the ellipse frac{x^(2)}{25} +frac{y^(2)}{4} =1 meets the axes at A and B then find the equation of the locus of middle point of AB.

In Delta ABC , if r_1 lt r_2 lt r_3 then

In DeltaABC, if r_(1) lt r_(2) lt r_(3) then

In Delta ABC , if r_(1) lt r_(2) lt r_(3) , then find the order of lengths of the sides

In Delta ABC , if r_(1) lt r_(2) lt r_(3) , then find the order of lengths of the sides

In Delta ABC , if r_(1) lt r_(2) lt r_(3) , then find the order of lengths of the sides

In Delta ABC , if r_(1) lt r_(2) lt r_(3) , then find the order of lengths of the sides

The radii of two soap bubbles are r_(1) and r_(2) (r_(2) lt r_(1)) . They meet to produce a double bubble. The radius of their common interface is