1 files changed, 40 insertions, 0 deletions
diff --git a/257/CH8/EX8.12/example_8_12.sce b/257/CH8/EX8.12/example_8_12.sce
new file mode 100644
index 000000000..ca0e2964c
--- /dev/null
+++ b/257/CH8/EX8.12/example_8_12.sce
@@ -0,0 +1,40 @@
+s=%s
+F=s^3+4*s^2+13*s+50
+
+disp(routh_t(F)) 
+r=coeff(F)
+routh=routh_t(F)
+n=length(r)
+c=0;
+for i=1:n
+if (routh(i,1)<0)
+c=c+1;
+ end 
+  end
+  if(c>=1)
+    printf("system is unstable")
+  else printf("there are no roots on RHS")
+  end
+syms s k
+G=5*k/(s*(1+s/3)*(1+s/6)*18)
+H=1
+Kv=limit(s*G*H,s,0)
+disp(Kv, " Kv = ")
+
+s=%s
+F=s^3+9*s^2+18*s+180
+
+disp(routh_t(F)) 
+r=coeff(F)
+routh=routh_t(F)
+n=length(r)
+c=0;
+for i=1:n
+if (routh(i,1)<0)
+c=c+1;
+ end 
+  end
+  if(c>=1)
+    printf("system is unstable")
+  else printf("there are no roots on RHS")
+  end