=============вычислите...........

Question

=============вычислите...........

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Answer 1

=7/√2 - (cos(90-15)cos15-cos15cos(90+15))/(sin18sin(90-27)+sin(90+18)sin27)=
=7/√2-(sin15cos15+cos15sin15)/(sin18cos27+cos18sin27)=
=7/√2- sin(15+15)/sin(18+27)=7/√2 - sin30/sin45=7/√2 - 1/2 :√2/2=7/√2 -1/√2=6/√2=
=6√2/2=3√2

Comments

спасибо