Question:
Using the formula for squaring a binomial, evaluate the following:
(i) (54)2
(ii) (82)2
(iii) (103)2
(iv) (704)2
Solution:
We shall use the identity (a+b)2 =a2 +b2 +2ab.
(i) $(54)^{2}$
$=(50+4)^{2}$
$=(50)^{2}+2 \times 50 \times 4+(4)^{2}$
$=2500+400+16$
$=2916$
(ii) $(82)^{2}$
$=(80+2)^{2}$
$=(80)^{2}+2 \times 80 \times 2+(2)^{2}$
$=6400+320+4$
$(82)^{2}$
$=(80+2)^{2}$
$=(80)^{2}+2 \times 80 \times 2+(2)^{2}$
$=6400+320+4$
$=6724$$=6724$
(iii) $(103)^{2}$
$=(100+3)^{2}$
$=(100)^{2}+2 \times 100 \times 3+(3)^{2}$
$=10000+600+9$
$=10609$
(iv) $(704)^{2}$
$=(700+4)^{2}$
$=(700)^{2}+2 \times 700 \times 4+(4)^{2}$
$=490000+5600+16$
$=495616$