Question

Let U = 5i+12j, V = -4i+j and W = i - 4j find:
|2V-W|

Answer 1

|2(-4i+j)-(i-4j)|

Answer 2

yup! i got that

Answer 3

but the answer came out to be root of 117 and I don't get how they got that :|

Answer 4

wow

Answer 5

idk then, sorry

Answer 6

it's fine thanks :D

Answer 7

take the magniutde of the resulting vector

Answer 8

I think i did the adding wrong or something
would it be |-8i+2j-1-4j|

Answer 9

and would that become |-9i+6j| ?

Answer 10

yes... now just take the magnitude...
sqrt((-9)^2 + (6)^2 )

Answer 11

you can't root a negative right ?

Answer 12

(-9)^2 = 81

Answer 13

(-9)^2 = (-9)*(-9) = 81

Answer 14

Ohhh i keep punching it in the calculator and it came out to be -81 but now that i think of it, negative x negative = positive, stupid me =.=

Answer 15

thanks @dpalnc

Answer 16

very common.. just so you know, the calculator does order of operations...
if you entered -9^2, the calculator will do 9*9 and then take the opposite of the answer.

Answer 17

yw

Answer 18

Ok!