Write the expression as a complex number in standard form 7 over 3 + i

Question

anonymous · Answer

Multiply top and bottom by conjugate? I'm assuming you mean make the denominator real when you say standard form.

anonymous · Answer

Yeah I guess, I really do not get it at all

anonymous · Answer

Are you familiar with complex conjugates?

anonymous · Answer

no, not at all

anonymous · Answer

Ok, the idea is this: if you have a complex number in the form a+bi, when you multiply it by a-bi, you get a real number. Try it for yourself.

anonymous · Answer

alright

anonymous · Answer

If you're not convinced, ask me and I'll show you.

anonymous · Answer

in fact you should just remember that 
$$(a+bi)(a-bi)=a^2+b^2$$ because it comes up quite frequently

anonymous · Answer

I feel stupid but I do not get it at all

anonymous · Answer

Don't worry.$$(a+bi)(a-bi)=a^2+abi-abi-b^2i^2=a^2-b^2i^2=a^2-b^2\times(-1)=a^2+b^2$$Is that clearer?

anonymous · Answer

I don't know which number represents each letter

anonymous · Answer

That doesn't matter at the moment. All I'm saying is that it works for any a and b.