Question

Hey, Mates,
Answer pls​

Answer 1

(a + ib)(c + id)(e + if)(g + ih) = A + iB

take modulus both sides,

|(a + ib)(c + id)(e + if)(g + ih)| = |A+iB|

we know,

|z1.z2.z3.......zn| = |z1|.|z2|........|zn| use this here,

|a+ib|.|c+id|.|e+if|.|g+ih| = |A+iB|

we also know,

|x + iy| = √(x²+y²) use it here,

√(a²+b²).√(c²+d²).√(e²+f²).√(g²+h²) = √(A²+B²)

squaring both sides,

(a²+b²).(c²+d²).(e²+f²).(g²+h²) = A²+B²

hence, proved//