Tyiesha says that if the magnitude of a vector u is zero, then u has to be a zero vector. is she correct? explain how

Yes ,Tyiesha is correct.

Step-by-step explanation:

Lets take u vector

u =  ai + b j +ck

So the magnitude of vector u given as

If the magnitude of above vector is zero then the values  a= 0 , b= 0 and c=0 should be zero.

a= 0 , b = 0 ,c = 0

So now by putting the values

u =  ai + b j +ck

u =  0 i + 0 j +0 k

u = 0  ,u is a zero vector.

It means that u should be zero vector.So Tyiesha is correct.

b

step-by-step explanation:

a difference is the result of subtraction. while each of these expressions has subtraction in it, a difference will be the result when subtraction is the last operation applied in the order of operations for the expression. this means subtraction must be outside of the parenthesis. only b has this.