the third, sixth and seventh terms of a
geometric progression (whose common
ratio is neither 0 nor 1 ) are in
arithmetic progression . prove that the
sum of the first three terms is equal to
fourth .
given that the parametric equation of
a curvd are x=(1/(t−1)) y=(1/(t+1)) obtaun a
cartesian equation of the curve. Hemce find
an equqtion of tbe nirmal to the curve at the
point t=2