Expand: (i) (5x^2-y^2+z^2)^2 (ii)(x+2y+7z)^2 (iii) (2p+3q-3r)^2 || Find Squares of Each of the Following (i) (5x2-y2+z2)2 (ii)(x+2y+7z)2 (iii) (2p+3q-3r)2
(i) (5x2-y2+z2)2
= {(5x2) +(-y2) +(z2)}2
= (5x2)2 +(-y2)2+(z2)2 +2 .5x2 .(-y2) +2.(-y2).(z2) +2.(z2).(5x2)
= 25x4 +y4+z4-10x2y2-2y2z2+10z2x2 [Ans]
(ii)(x+2y+7z)2
= (x)2+(2y)2+(7z)2 +2. x . 2y +2 . 2y . 7z +2 . 7z . x
=x2+2y2+49z2+4xy+28yz+14zx [Ans]
(iii) (2p+3q-3r)2
=(2p)2+(3q)2+(-3r)2 +2 . (2p) . (3q) +2 . (3q) . (-3r) + 2(-3r) (2p)
=4p2+9q2+9r2 +12pq – 18qr -12pr [Ans]