Use a transformation to solve the equation. –3d = –27 A. d = –30 B. d = –24 C. d = –9 D. d = 9
2 answers:
You might be interested in
One could use the relation
where
are two vectors, 
denotes the norm of that vector, and 
is the angle between the two vectors.
Then the two vectors will be parallel if
or 
.
where
Then the two vectors will be parallel if
a. Notice that
1/(1*2) = 1/2 = 1 - 1/2
1/(2*3) = 1/6 = 1/2 - 1/3
1/(3*4) = 1/12 = 1/3 - 1/4
and so on, which suggests the n-th term of the sum can be written as
Then the sum itself is telescoping:
b. The proof is trivial:
so the formula found in (a) is correct.