Darius wants to purchase his favorite salad dressing. the salad dressing comes in two different size bottles. the 16 ounce bottle is on sale for $3.36. the 10 ounce bottle is priced at $2.30. darius has a coupon for 40 cents off if you buy two 10 ounce bottles. determine if darius gets the better buy when he buys one 16 ounce bottle or when he buys two 10 ounce bottles. a. darius will get the same deal on either purchase. b. darius will get the better deal buying one 16 ounce bottle. c. darius will get the better deal buying two 10 ounce bottles. d. darius doesn’t need the coupon, he will get the best deal on one 10 ounce bottle.

the value of v.w= -12.

step-by-step explanation:

we are given three vector r,v and w as:

r = < 5, -5, -2> ; v = < 2, -8, -8> ; w = < -2, 6, -5>

we know that r,v and w could also be represented as:

r=5i-5j-2k

v=2i-8j-8k

and w= -2i+6j-5k

where i,j and k are the unit vectors of x,y and z-axis respectively.

also we know that it has the following property:

i.i=1 ; j.j=1; k.k=1

and i.=j.i=i.k=k.i=j.k=k.j=0

i.e. when we multiply two vectors or we find it's dot product we need to only multiply the components of x coordinates with each other; y with each other and z with each other.

hence, v.w= (2i-8j- -2i+6j-5k)

                  = 2×(-2)+(-8)×(6)+(-8)×(-5)

                  = -4-48+40

                  = -12

hence, v.w= -12

17.08

correct me if i am wrong.