Without a computer or calculator, match the equations (a)--(f) with the graphs (1)-(6) below. (a) z = cos(Vx2+ y2) : ? v (b) z = (2x2 + 32) el-12-1 : ? (c) z = sin (z) + y? /4: ? ~ (d) z = y/4: ? (e) z = sin(x] + ly|) : ? (f) z = x - cos(y) : ? 1. 2. 3. 4. 5. 6