Q. If x+y+z=0, show that x³+y³+z³=3xyz.
Sol:
Given,
=>x+ y+ z=0
=>x+ y = - z_______(1)
=>(x+y)³=( - z)³
=>x³+y³ - 3xy(x+y)= - z³
=>x3+y³ - 3xy( - z)= - z³ [from eqn (1)]
=>x³+y³ - 3xyz= - z³
=>x³+y³+z³=3xyz
__
Q. Express 4.035 in the form of p/q.
Sol: __
Let, x=4.035
=> x = 4.0353535........
=>10x=40.353535......._____(1)
=>1000x=4035.3535.....____(2)
So, (2) - (1)
=>990x=3995
=> x = 3995/990
=> x = 799/198
