Question

If a=3 and b=4, Then find value of
ab+ba​

Answer 1

Answer:

a+λb is perpendicular to a−λb

∴(a+λb).(a−λb)=0

∣a∣2−λ×(a.b)+λ×(b.a)−λ2×∣b∣2=0

⇒∣a∣2−λ2×∣b∣2=0

λ=±∣b∣∣a∣=±43

Answer 2

Answer:

ab+ba

(3)(4)+(4)(3)

12 + 12

24