Question

If a=6i+6j-3k and b=7i+4j-4k then angle between a and b is

Answer 1

Answer:

45

Step-by-step explanation:

|a|=UNDER ROOT(6+6+3)=under root (15)

|b|=under root (7+4+4)=under root(15)

tan(theta)=|a|/|b|=1

(theta)=45

Answer 2

a= 6i +6j -3k

b= 7i+4j+4k

now , we know that in this case

a.b= ab×cosX ,where X is the angle between a and b .

therefore,angle between a and b is cos^-1(78/81).