<p>I'm using the generic book for all of the SAT II's, not the math-specific one. Can someone please explain to me how to get the answers to 45, 47, 48, 49, and 50??!?! :)</p>
<p>thanks mucho</p>
<p>i'll be on this board for another hour or so...but i dont have the book. if you can type a question i can show you dont bother doing answer choices</p>
<p>KK thanks ^_^</p>
<p>Nevermind, I get number 45.</p>
<p>47: Which of the following shifts of the graph of y=x^2 would result in the graph of y =x^2 -2x + k, where k is a constant greater than 2?</p>
<p>I get 48, too.</p>
<p>49: If matrix A has dimensions m x n and matrix B has dimensions n x p, where m, n, and p are distinct positive integers, which of the following statements must be true?</p>
<p>I. The product BA does not exist
II. The product AB exists and has dimensions m x p
III. The product AB exists and has dimensions n x n</p>
<p>50 is a graph</p>
<p>Thanks :)</p>
<p>47) i would use graphic calculator... it should be a curve with no zeros that is obliquely moved in the +x and +y direction
49) i havent encountered matrices on any other tests, doubtful they will come up...
that question is just testing you knowledge of the definition of matrix multiplication. (the key is to know that the number of rows must equal number of columns or vice versa)
if A is m x n and B is n x p, then AB exits (since n=n)... now BA is (n x p)(m x n) this doesnt exist since p isnt equal to m
Now... as for the dimensions, they are m x p (again you have to know how to carry out the matrix multiplication to know this</p>
<p>so your answer is I, II are true III is false</p>
<p>NOW TO SUMMARIZE:
AB is defined if and only if # of row = # column or # col = # now
that is (a x b)(b x c) is defined
and the solution to this is
a x c matrix</p>