1.

If the sides of triangle `ABC` are in G.P with common ratio `r (r

Answer» it is given that a,b,c are in GP
a=1, b=r, c=`r^2`
sum of two sides is always greater than the third side
(a+b)>c
(1+r)>`r^2`
`r^2-r-1<0`
r=`(1+-sqrt(1+4))/2`
r=`(1+-sqrt(5))/2`
`(r-(1+sqrt5/2))(r-(1-sqrt5/2))`<0
let r=0
`((1+sqrt5)(1-sqrt5))/2`
`(1^2-5)/2=-4/2=-2<0`
`r in ((1-sqrt5)/2,(1+sqrt5)/2))`
so,
`r<1/2 (1+sqrt5)`


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