Q1 of 59 Page 7

Expand the following

(5x + 2y + 3z)2

(5x + 2y + 3z)2


The identity is


(x + y + z)2 = x2 + y2 + z2 + 2xy + 2yz + 2zx


∴ (5x + 2y + 3z)2


= (5x)2 + (2y)2 + (3z)2 + 2(5x)(2y) + 2(2y)(3z) + 2(3z)(5x)


= 25x2 + 4y2 + 9z2 + 20xy + 12yz + 30zx


More from this chapter

All 59 →
1

Expand the following

(2a + 3b – c)2

 1

Expand the following

(x – 2y – 4z)2

 1

Expand the following

(P – 2q + r)2

 2

Find the expansion of

(x + 1)(x + 4)(x + 7)