As acer noted in his comment, maple syntax doesn't use square brackets for functions. The proper syntax for your task is:
int(1/sqrt(cos(t)-cos(Pi/4)),t=0..Pi/4);
Notice that maple works in radians, so I replaced your 45
with Pi/4
.
If you need a numerical value you can use evalf
:
evalf(int(1/sqrt(cos(t)-cos(Pi/4)),t=0..Pi/4));
maple's answer is 2.310196615
.
If you need to evaluate with a generic variable theta0
, you can define a function as:
myint:=theta0->int(1/sqrt(cos(t)-cos(theta0)),t=0..theta0);
Then just call it as, e.g.,
myint(Pi/4);
and for a numerical evaluation:
evalf(myint(Pi/4));