Question

for 2 real vectors a and b prove that (vector a + vectorb)²= vector a²+ vector b²+2ab​

Answer 1

Answer:

a x b= a b sin∅ .n, where a=lal and b=lbl

(а х b)² = a² b² sin² (n)² = a² b² sin²∅

a²b²(1-cos²∅)=a² b² - a² b² cos²∅

lal² lbl² -(a.b)²

(∵ (n)²=1)

Step-by-step explanation: