Find the inner product for (7.2) (0,-2) and state whether the vectors are perpendicular.

a. -4; no

c. 4; no

b. -4; yes

d. 4; yes

a. -4; no

Step-by-step explanation:

Suppose we have two vectors, a and b.

a = (1,2)

b = (2,3)

Their inner product is:

a.b = (1,2).(2,3) = 1*2 + 2*3 = 8

The vectors are perpendicular if their inner product is 0.

In this question:

a = (7,2)

b = (0,-2)

So

a.b = (7,2).(0,-2) = 7*0 + 2*(-2) = -4

-4 is different of 0, so they are not perpendicular.

So the corret answer is:

a. -4; no

its 50 miles away from the starting point

hello from mrbilldoesmath!

answer:   (7x + 6y) ( 49x^2 - 42xy + 36y^2)

discussion:

in general, the factorization of a^3 + b^3 is

a^3 + b^ 3 = (a + b) ( a^2 - ab + b^2)

in our case note that 343 = 7^3 and 216 = 6^3 so the equation becomes:

343x^3 + 216y^3 = (7x)^3 + (6y)^3

if you think of a (above) as 7x and b as 6y the factorization becomes

343x^3 + 216y^3 =

((7x + 6y) (   (7x)^2 - 7x*6y + (6y)^2)   =

(7x + 6y) ( 49x^2 - 42xy + 36y^2)

you,

mrb

(a + b) (a^2 - a b + b^2)