maths 解方程...

(5a^2+a+3)(x-2)
=5a^2x+ax+3x-10a^2-2a-6


(根本唔洗計 睇e緊計到 呢d數最多計到20秒)

( 5 a^2 + a + 3 ) ( x - 2 )
=x(5a^2)+x(a)+x(3)-2(5a^2)-2(a)-2(3)
=5a^2x+ax+3x-10a^2-2a-6
=ax+5a^2x-10a^2+ax-2a+3x-6

( 5 a^2 + a + 3 ) ( x - 2 )

= 5a^2(x-2)+a(x-2)+3(x-2)

=5a^2x-10a^2+ax-2a+3x-6

( 5 a^2 + a + 3 ) ( x - 2 )
=( 5 a^2x + ax + 3x ) + ( -10 a^2 -10 a -6 )
=5 a^2x-10 a^2 + ax + 3x -10 a -6