i have problem in uses of inline or syms ordes

i want have a variable like x that define on x ,f(x) function,then program does math operators on f(x) and compute the result of this operators for specified x,

for example in During the a code i want define x with syms order and obtain f=x^2+x+1, then compute f(1)^2

Answer 1

[Walter Roberson]

syms x
f = x^2+x+1;
subs(f^2,x,1)

[xosro]

tahnks mr.Walter Roberson

[xosro]

your answer has was correct but matlab does not know answer of subs(y^2,x,1) as a logic number for example when i run

>>syms x
>>f = x^2+x+1;
>>subs(f^2,x,1)
>>ans=
>> ans>1

ans =

1 < 9

[Walter Roberson]

The result of a computation with symbolic values is a symbolic value. If you want the closest floating point equivalent, double() the symbolic value. For example,

double(subs(f^2,x,1))