1 files changed, 11 insertions, 0 deletions
diff --git a/40/CH4/EX4.12/Exa_4_12.sce b/40/CH4/EX4.12/Exa_4_12.sce
new file mode 100755
index 000000000..4ec3cd076
--- /dev/null
+++ b/40/CH4/EX4.12/Exa_4_12.sce
@@ -0,0 +1,11 @@
+//inverse z transforms from standard transforms
+z=%z;
+xz=z/((z-0.5)*(z-0.25));
+yz=xz/z;
+pfss(yz)
+//hence x[n]=-4(0.25)^n*un+4(0.5)^n*un;
+xz=1/((z-0.5)*(z-0.25));
+yz=xz/z;
+pfss(yz)
+//hence x[n]=-4(0.25)^n-1*u[n-1]+4(0.5)^n-1*u[n-1];
+