\[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right)\]
\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right)
double f(double a1, double a2, double th) {
        double r65952 = th;
        double r65953 = cos(r65952);
        double r65954 = 2.0;
        double r65955 = sqrt(r65954);
        double r65956 = r65953 / r65955;
        double r65957 = a1;
        double r65958 = r65957 * r65957;
        double r65959 = r65956 * r65958;
        double r65960 = a2;
        double r65961 = r65960 * r65960;
        double r65962 = r65956 * r65961;
        double r65963 = r65959 + r65962;
        return r65963;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019323 
(FPCore (a1 a2 th)
  :name "Migdal et al, Equation (64)"
  :precision binary64
  (+ (* (/ (cos th) (sqrt 2)) (* a1 a1)) (* (/ (cos th) (sqrt 2)) (* a2 a2))))

Backtrace

get-representation: Unknown representation realLC
(unnamed)/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/regimes.rkt653
filter/opt/racket-7.2/collects/racket/private/list.rkt2562
infer-splitpoints/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/regimes.rkt340
get-final-combination/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt3690
(unnamed)/opt/racket-7.2/collects/racket/private/more-scheme.rkt26128
run/opt/racket-7.2/share/pkgs/profile-lib/main.rkt392
profile-thunk16/opt/racket-7.2/share/pkgs/profile-lib/main.rkt90
(unnamed)/opt/racket-7.2/collects/racket/private/more-scheme.rkt26128