What is the value of ∣∣J∣∣?
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Answer:
2 sqrt(30)
Step-by-step explanation:
We want to find the norm of the matrix
( -2 6
4 8)
Take the square root of the sum of the squares
sqrt( (-2) ^2 + 6^2 + 4^2 + 8^2)
sqrt( 4+36+16+64)
sqrt( 120)
sqrt( 4*30)
2 sqrt(30)