А (sin³a+cos³a):(sina+cosa)+sinacosa= =(sina+cosa)(sin²a-sinacosa+cos²a)/(sina+cosa)+sinacosa=1-sinacosa+sinacosa=1 1=1 б (1+2sinbcosb)/(cosb+sinb)²= =(cos²b+sin²b+2sinbcosb)/(cos²b+2cosbsinb+sin²b)=1 1=1 в (sin^4b-cos^4b)/(cos²b-sin²b)=(sin²b-cos²b)(sin²b+cos²b)/(cos²b-sin²b)=-1 -1=-1 г
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А(sin³a+cos³a):(sina+cosa)+sinacosa=
=(sina+cosa)(sin²a-sinacosa+cos²a)/(sina+cosa)+sinacosa=1-sinacosa+sinacosa=1
1=1
б
(1+2sinbcosb)/(cosb+sinb)²=
=(cos²b+sin²b+2sinbcosb)/(cos²b+2cosbsinb+sin²b)=1
1=1
в
(sin^4b-cos^4b)/(cos²b-sin²b)=(sin²b-cos²b)(sin²b+cos²b)/(cos²b-sin²b)=-1
-1=-1
г