<p>These problems have to do with the complex conjugates theorem.
x=r+si
z=u+vi
The conjugate of x=r-si
The conjugate of z=u-vi</p>
<p>1) Prove that the conjugate of (x+z)= the conugate of x plus the conjugate of z.
2) Prove that the conjucate of (xz)= the conugate of x times the conjuagte of z</p>
<p>Please explain your work as I am still not understanding how to find the conjucate of r+si+u+vi, in number 1.</p>
<p>1) To find the conjugate of r+si+u+vi, group the terms that are the same.
-- So (r+u) + (si+vi)
-- Then factor out an i: (r+u) + (s+v) i
-- So the conjugate is: (r+u) - (s+v) i
-- And simplify: (r+u) - (si + vi)
-- Simplify again: r+u-si-vi
And that's the same as conj. of x (r-si) plus conj. of z (u-vi) which is (r-si+u-vi)</p>
<p>Do the same thing for #2.. multiply, then group the terms that are the same. Then factor out an i and find the conjugate, then simplify.</p>