Упростить.sin^2(П/8)+cos^2x9П/8+sin^2x5ППо формуле приведений.

[latex] sin^{2} \frac{ \pi }{8}+ cos^{2} \frac{9}{8} \pi + sin^{2}5 \pi = sin^{2} \frac{ \pi }{8}+ cos^{2}( \pi + \frac{ \pi }{8})+ sin^{2}(4 \pi + \pi )= \\= sin^{2} \frac{ \pi }{8}+ cos^{2} \frac{ \pi }{8}+ sin^{2} \pi = sin^{2} \frac{ \pi }{8}+ cos^{2} \frac{ \pi }{8}+0= sin^{2} \frac{ \pi }{8}+ cos^{2} \frac{ \pi }{8}=1 [/latex]