What is: 

2 + 4( 3, 2, 5)T

A good answer might be:

(Trick Question!) The expression is ill-formed. There is no operator + that does this: real number + vector


Expressions with Mixed Types

It is helpful to use parentheses to show exactly what you mean in expressions containing mixed types and operators. Look at this: 

(2 + 1)(3, -5)T + 4(1, 2)T

The first "+" is scalar addition; the second "+" is column matrix addition. You should perform the operations like this: 

(2 + 1)(3, -5)T + 4(1, 2)T   = 

3(3, -5)T + 4(1, 2)T   = 

(3*3, 3* -5)T + (4*1, 4*2)T 

 = 

(9, -15)T + (4, 8)T  =  (13, -7)T

This is not as bad as it looks, as long as you keep track of what operators you have available, what types of operands they take, and what their results are.

QUESTION 5:

Evaluate the following: 

-1 (1, 2, -3)T - (2 + 1)(1, 0, 1)T