Answer :
Answer:
The value of -8u-2v is:
28i+56j or in vector form it is: <28,56>
Step-by-step explanation:
We are given two vectors u and v such that:
u = <-5, -9> and v = <6, 8>.
In vector form it could be represented as:
u=-5i-9j, where i and j represents the unit vector in the direction of x and y axis respectively.
and v=6i+8j
Now we are asked to find the value of:
-8u - 2v.
We know that -8u could be written as:
-8u=-8(-5i-9j)
⇒ -8u=(-8)×(-5)i+(-8)×(-9)j
⇒ -8u=40i+72j
Also -2v is given as:
-2v=-2(6i+8j)
⇒ -2v= (-2)×6i+(-2)×8j
⇒ -2v= -12i-16j
Hence the value of -8u - 2v is:
-8u-2v= 40i+72j-12i-16j
⇒ -8u-2v= 28i+56j
Hence in vector form it could be written as:
<28,56>.
Answer:
<28,56>
Step-by-step explanation:
We have given two vectors and we have to simplify according to given expression.
Given vectors are:
u = <-5,-9> and v = <6,8>
Since, we know that
<a,b> represents vectors ai+bj where i and j are unit vectors along x and y-axis.
Applying above formula on given vectors :
u = -5i-9j and v = 6i+8j
-8u-2v = -8(-5i-9j)-2(6i+8j)
-8u-2v = 40i+72j-12i-16j
Adding like vectors, we have
-8u-2v = (40-12)i+(72-16)j
-8u-2v = 28i + 56j
Hence -8u-2v = <28,56> which is the answer.