Question

Show that, |a×b|^2 = a^2b^2-(a.b)^2​

Answer 1

Is it multiply sign between a*b

Answer 2

Hey mate,..

Given-

    [a+b]^2 = 2a^2 + 2b^2

Then we have to show that    a=b

Now as we know that -

                           [a+b]^2 = a^2 + 2ab + b^2 --------------------  (i)

so, now according to question 

                            [a+b]^2 = 2a^2 + 2b^2 ------------------------ (ii)

using equation (I) and (ii) we get 

                2a^2 + 2b^2 =  a^2 + 2ab + b^2

         or,        a^2 + b^2    = 2ab

        or, a^2 - 2ab + b^2   = 0

         or,   [a - b]^2           = 0     [using the formula [a-b]^2 = a^2 + 2ab + b^2 ]

so,                        a - b   = 0

Hence                   a = b proved.

Hope it will help you.

✨sai.