math

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what angle between vectors u = 2j+2k & v= 3i+4k
Gracias por ayudarme

• math -

u.v = |u| * |v| * cosθ

cosθ = (6+8)/(2√2)(5) = 14/10√2
θ = 8.13°

• math -

u dot v = |u| |v| cos(theta)

u dot v = 6

|u| = 2 sqrt(2)

|v| = 5

cos(theta) = 3/[5 sqrt(2)]

• math -

Correction u dot v = 8, so

cos(theta) = 4/[5 sqrt(2)]

• math -

but isn't is a three dimensional vectors

• math -

Count Iblis is correct.

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