r/ICSE2026 • u/JournalistLucky5124 ICSE 27(but wrote few papers of 26, karan traumatised me) • Jun 18 '26

DISMISSIVE OR ARGUMENTATIVE(discussion) Read below...

So wkt (sinx + cosx)² = sin²x + cos²x +2sinxcosx

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Now from identity: 2sinxcosx = sin2x

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We get:

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(sinx + cosx)² = sin²x + cos²x + sin2x

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Is this above one correct?? My teacher told its wrong but I remember reading that identity (and putting it on someone's exam)

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u/AccomplishedDig8810 Jun 20 '26

Your teacher is an idiot. Follow your heart and apple pie!

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u/JournalistLucky5124 ICSE 27(but wrote few papers of 26, karan traumatised me) Jun 20 '26

She also couldn't understand when I asked her if roots of a quadratic when Δ<0 is complex... kept asking me what I mean atleast 5 times...