sin cos tan cot 1 sec^4 - sec² 化简成 1/cot4 + 1/cot²2 sec/cos - tan/cot 化简成 13 (1-2cos²)/(sincos) 化简成 tan - cot

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sin cos tan cot 1 sec^4 - sec² 化简成 1/cot4 + 1/cot²2 sec/cos - tan/cot 化简成 13 (1-2cos²)/(sincos) 化简成 tan - cot

sin cos tan cot 1 sec^4 - sec² 化简成 1/cot4 + 1/cot²2 sec/cos - tan/cot 化简成 13 (1-2cos²)/(sincos) 化简成 tan - cot
sin cos tan cot
1 sec^4 - sec² 化简成 1/cot4 + 1/cot²
2 sec/cos - tan/cot 化简成 1
3 (1-2cos²)/(sincos) 化简成 tan - cot

sin cos tan cot 1 sec^4 - sec² 化简成 1/cot4 + 1/cot²2 sec/cos - tan/cot 化简成 13 (1-2cos²)/(sincos) 化简成 tan - cot
sin^2+cos^2=1
1.sec^4-sec^2=(1/cos^4)-1/(cos^2)=(sin^2)/(cos^4)
=[(sin^2)*(sin^2+cos^2)]/cos^4=1/cot4 + 1/cot²
2.sec/cos - tan/cot=1/(cos^2)-(sin^2)/(cos^2)=cos^2/cos^2=1
3.(1-2cos²)/(sincos) =(sin^2+cos^2-2cos^)/(sincos)=(sin^2-cos^2)/(sincos)=tan - cot

1.sec^4 - sec² =1/cos^4-1/cos^2=
(1-cos^2)/cos^4=sin^2/cos^4=(sin^4+sin^2-sin^4)/cos^4
=sin^4/cos^4+(sin^2-sin^4)/cos^4
=tg^4+sin^2*cos^2/cos^4
=1/cot^4+sin^2/cos^2=1/cot^4 + 1/co...

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1.sec^4 - sec² =1/cos^4-1/cos^2=
(1-cos^2)/cos^4=sin^2/cos^4=(sin^4+sin^2-sin^4)/cos^4
=sin^4/cos^4+(sin^2-sin^4)/cos^4
=tg^4+sin^2*cos^2/cos^4
=1/cot^4+sin^2/cos^2=1/cot^4 + 1/cot^2
2.sec/cos - tan/cot =1/cos^2-sin^2/cos^2
=cos^2/cos^2=1
3.(1-2cos^2)/(sincos) =(sin^2+cos^2-2cos^2)/sincos
=(sin^2-cos^2)/sincos=sin^2/sincos-cos^2/sincos
=sin/cos-cos/sin=tan - cot

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