Question

show that (a vector - b vector ) × ( a vector + b vector ) = 2 ( a vector × b vector)​

Answer 1

Answer:

QUESTION:

(a vector - b vector ) × ( a vector + b vector ) = 2 ( a vector × b vector)

FORMULAS USED:

• $\sf \overrightarrow{b} \times \overrightarrow{a} = - \overrightarrow{a} \times \overrightarrow{b}$
• vector multiplication of same digit zero.

STEPS USED:

• In first step multiply the vectors in left hand side
• vector a × vector a is zero
• vector b× vector b is zero
• $\sf \overrightarrow{b} \times \overrightarrow{a} = - \overrightarrow{a} \times \overrightarrow{b}$
• then add them

then the answer will be

$2(\overrightarrow{a} \times \overrightarrow{b}) \\ \\ { \bold {\boxed{Hence \: proved}}}$