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Given that r=2ij, s=3i+5j and \(t = 6i - 2j...

Given that r=2ij, s=3i+5j and t=6i2j, find the magnitude of 2r+st.

A.

15

B.

4

C.

24

D.

26

Correct answer is D

r=2ij,s=3i+5j,t=6i2j

2r+st=2(2ij)+(3i+5j)(6i2j)=i+5j

|2r+st|=12+52=26