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prove that if the sum and diffrence of two vectors are perpendicular then the vectors have equal magnitude?​

User Ouarzy
by
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1 Answer

5 votes

Answer:

true.

Step-by-step explanation:

Using the fact that the dot product of two perpendicular vectors is equal to zero:


(\overrightarrow{a}+\overrightarrow{b})\cdot (\overrightarrow{a}-\overrightarrow{b}) = 0\\\overrightarrow{a}\cdot\overrightarrow{a}-\overrightarrow{b}\cdot\overrightarrow{b}=0\\\overrightarrow{a}\cdot\overrightarrow{a}=\overrightarrow{b}\cdot\overrightarrow{b}\\|a|^2=|b|^2\\|a|=|b|

User Aayush Agrawal
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6.3k points