PDF chapter test TRY NOW

The function from \(A\) \(=\) \(\{\)2, 8, 13, 19\(\}\) to \(B\) \(=\) \(\{\)\(37\), \(25\), \(15\), \(3\)\(\}\)  is represented by the table below, where \(f(x)\) \(=\) \(2x\) \(-\) \(1\).
 
\(x\)
2
8
13
19
\(y\)
\(a\)
\(15\)
\(25\)
\(b\)
 
Find the values of \(a\) and \(b\).
 
\(a\) \(=\)
 
\(b\) \(=\)