Question

find sngle between a=4i + 6j -7k and b=3i + 6j - 7j find ab​

Answer 1

Answer:

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Explanation:

Let a = ( 4 , -2 , 4 ) and b = ( 3 , 6 , -2 )

So:

(a • b) = 12 -12 -8 = - 8

|a| = √ ( 16 + 4 + 16 ) = √ 38 = 6.1644

|b| = √ ( 9 + 36 + 4 ) = √49 = 7

Cosθ = [(a • b) / |a| |b|] =( - 8) /(6.1644*7) = ( - 8)/(43.1508)