Question 942308


{{{(x-5-5i)(x-5+5i)}}} 

1.first multiply {{{(x-5+5i)}}} by {{{x}}} from {{{(x-5-5i)}}}:

{{{x(x-5+5i)}}}=>{{{(x^2-5x+5x*i)}}}...(1)

2.then multiply {{{(x-5+5i)}}} by {{{-5}}}:

{{{-5(x-5+5i)}}}=>{{{(-5x+25-25i)}}}...(2)

3.then multiply {{{(x-5+5i)}}} by {{{-5i}}}:

{{{-5i(x-5+5i)}}}=> {{{(-5x*i+25i-25i^2)}}}...(3)

now just put (1),(2) and (3) together

so, it will be:

{{{(x-5-5i)(x-5+5i)=(x^2-5x+5x*i)+(-5x+25-25i)+(-5x*i+25i-25i^2)}}}...recall {{{i^2=-1}}}

{{{(x-5-5i)(x-5+5i)=x^2-5x+5x*i-5x+25-25i-5x*i+25i-25(-1)}}}

{{{(x-5-5i)(x-5+5i)=x^2-5x+cross(5x*i)-5x+25-cross(25i)-cross(5x*i)+cross(25i)-25(-1)}}}

{{{(x-5-5i)(x-5+5i)=x^2-5x-5x+25-25(-1)}}}

{{{(x-5-5i)(x-5+5i)=x^2-10x+25+25}}}

{{{(x-5-5i)(x-5+5i)=x^2-10x+50}}}