the-vectors-a-and-b-are-such-that-a-3-b-5-and-a-b-14-find-a-b-

Question Number 64348 by Rio Michael last updated on 16/Jul/19

t h e v e c t o r s a a n d b a r e s u c h t h a t ∣ a ∣ = 3, ∣ b ∣= 5 a n d a . b = - 14

f i n d ∣ a - b ∣

Answered by Tanmay chaudhury last updated on 17/Jul/19

∣ a - b ∣^{2} = (a - b) . (a - b)

= a . a - 2 a . b + b . b

=∣ a ∣^{2} - 2 a . b + ∣ b ∣^{2}

= 9 + 28 + 25

∣ a - b ∣= \sqrt{62}