PDA

View Full Version : Vectors SAT Subject test Math level 2



Brynlee
12-30-2013, 05:34 AM
Vectors SAT Subject test Math level 2

Which of the following is the vector a-b given that a=(1,-2) and b=(3,-4)?

(A) (2,-2)
(B) (-2,2)
(C) (-2,-2)
(D) (2,2)
(E) (3,8)

Thanks!

Thomas
12-30-2013, 05:36 AM
Vector addition can be performed simply by adding the corresponding components of the vectors and in order to perform scalar multiplication, you need to multiply the scalar by each component of the vector.

a-b=(1,-2) -(3,-4) =(1-3,-2-(-4))=(-2,2)

Therefore the correct answer is (B)

Hope these help!!

Brynlee
12-30-2013, 05:37 AM
a-b=(1,-2) -(3,-4) =(1-3,-2-(-4))=(-2,2)

Therefore the correct answer is (B)

Hope these help!!

Thank you!!:D