Упростить выражение 1-Sin²t/1-Cos²t+tgt*ctgt

Mary lives in Alaska, but her daughters moved to Washington few years ago.

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Columbus discovered America in 1492. 

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A:  I’ve forgotten to tell Mary about the meeting.

B:  Don’t worry. I’ll call her right now.

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A:  Don’t call her now. She’s working on her project.

B:  How do you know?

A:  She always works when her children aren’t at home.

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What were you doing when you saw the thief?

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I was parking my car when that man ran out of the shop and jumped into a red car.

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I don’t think that your team  will win.

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While she was going home, it started to rain.

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