Question

Plz answer it quickly....
Answer with proper explanation will be marked as BRAINLIEST​

Answer 1

Answer:

the answer of this question is a because mm=-1

Answer 2

Answer:

Hey Mate, plz mark as BRAINLIEST!

Step-by-step explanation:

A and B  are two vector

A+B and A-B are perpendicular to each other.

We know that if two vectors(M and N) are perpendicular to each other then

M . N = |M|. |N| cos θ

Perpendicular θ =90°

 so cos 90° = 0

M . N = |M|. |N| cos θ = |M|. |N| x 0

M . N = 0

So we can say that

( A+B  ).(A-B ) = 0

A.A+B.A- A.B - B.B = 0            ( A.B=B.A)

A.A - B.B=0                          

So we can say that

|A| = |B|