Perform Operations with Vectors in Terms of I and J $\mathbf { u } = - 8 \mathbf { i } + 1 \mathbf { j }$

Multiple Choice

Perform Operations with Vectors in Terms of i and j
- $\mathbf { u } = - 8 \mathbf { i } + 1 \mathbf { j }$ and $\mathbf { v } = 5 \mathbf { i } + 1 \mathbf { j }$ ; Find $\| \mathbf { u } + \mathbf { v } \|$

A) $\sqrt { 13 }$
B) 13
C) $\sqrt { 91 }$
D) $3 \sqrt { 5 }$