a)
5 a + 10 a - 12 a - 4 a +5 a = 4 a
= 15 a - 12 a - 4 a + 5 a=
= - a + 5 a=
= 4 a
b)
x - 6 x + 10 x - 4 x - 3 x = - 2 x
= 5 x - 7 x =
= - 2 x
c)
7 a b - 4 a b + 13 a b + a b - 10 a b= 7a b
= 3 a b + 14 a b - 10 a b =
= 17a b - 10 a b =
= 7 a b
d)
1 / 2 xy + 1/3 xy + 1 / 6 xy= 1/xy
= 3/6xy + 2/6xy + 1/6xy =
= 6/6xy=
= 1/xy
e)
√ 2abc - 2√2abc + √2abc = 0
= - √2abc + √2abc=
= 0