1) eix 2) e-ix 3) ex 4) e-x Solution: (4) e-x cos ix + i sin ix = cos hx + i i sin hx = cos hx - sin hx = [ex + e-x - ex + e-x] / 2 = e-x... View Article
1) cos x cos hy 2) sin x sin hy 3) - sin x sin hy 4) cos x sin hy Solution: (1) cos x cos hy cos (x + iy) = A + iB cos x cos (iy) - sin x... View Article
1) a 2) b 3) [a + b] / [1 - ab] 4) [a - b] / [1 + ab] Solution: (4) [a - b] / [1 + ab] Put a = tan θ, b = tan ɸ and x = tan ψ, then reduced... View Article