Question

(15:1,2)•(7:1,4)-(1:2,5)•(3:1,2)=

Answer 1

(15:1,2)•(7:1,4)-(1:2,5)•(3:1,2)=61,5

1) 15:1,2=12,5

2) 7:1,4=5

3)1:2,5=0,4

4) 3:1,2=2,5

5)12,5*5=62,5

6)0,4*2,5=1

7)62,5-1=61,5

Answer 2

To evaluate the expression (15:1,2)•(7:1,4)-(1:2,5)•(3:1,2), let's break it down step by step.

First, let's compute the dot product between the vectors (15:1,2) and (7:1,4): (15:1,2)•(7:1,4) = 157 + 11 + 2*4 = 105 + 1 + 8 = 114

Next, let's compute the dot product between the vectors (1:2,5) and (3:1,2): (1:2,5)•(3:1,2) = 13 + 21 + 5*2 = 3 + 2 + 10 = 15

Now, we can subtract the second dot product from the first dot product: 114 - 15 = 99

Therefore, (15:1,2)•(7:1,4)-(1:2,5)•(3:1,2) equals 99.