a] Let the roots be a−d,a,a+d
3a=9⇒a=3
a2−ad+a2+ad+a2−d2=26
3a2−d2=26
3(9)−d2=26
⇒d=1
∴2,3,4
Product =k=24
b] Let the roots be ar,a,ar
a3=64⇒a=4
ar+a+ar=14⇒1r+r=52
⇒r=2 or r=12
k=a2r+a2r+a2=8+32+16=56
c] Let the roots be 1a−d,1a,1a+d
a−d+a+a+d=6616=6
a=2
Hence, 12 is a root of the equation.
⇒68−k4+3−1=0
⇒114=k4
k=11
3k=33
d) Let the roots be α,β,γ
α+β+γ=0
It is given that α+β=3
Hence, γ=−3