I need help with these trigonometry problems. I would really appreciate it if you could help me. Here is the problem: Problem #3 – Show that |r(cosθ + isinθ )| = r. Second Question: – Find the complex roots of z^4 + 256 = 0 and use them to factor the expression into irreducible quadratics with real coefficients.
l r(sinθ + isinθ) l = l rcosθ + irsinθ l
= √[(rcosθ)2 + (rsinθ)2] = √[r2(cos2θ + sin2 θ)] = √(r2) = r