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Advanced Math/proving trig identies
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Question
(sec theta-tan theta)(1+sin theta)=cos theta
(sec(A) - tan(A))(1 + sin(A))
((1/cos(A)) - (sin(A)/cos(A))(1 + sin(A))
((1 - sin(A))/(cos(A)))(1 + sin(A))
((1 - sin(A))(1 + sin(A)))/(cos(A))
(1 + sin(A) - sin(A) - sin(A)^2)/(cos(A))
(1 - sin(A)^2)/cos(A)
(cos(A)^2)/(cos(A))
cos(A)
so
(sec(A) - tan(A))(1 + sin(A)) = cos(A)
http://www.math.com/tables/trig/identities.htm
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Answers by Expert:
Sherman D.
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I can answer questions dealing in mathematics of all kinds except for Physics and Calculus, but i can answer questions in Pre-Calculus and Chemistry. I can also answer questions in Recipes of all kinds. I can find games cheats/walkthroughs, but i can`t find a specific game online or offline. I can also do history and recipes for alcoholic beverages.
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Mathematics, Recipes, History, and Games.
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High School graduated. I graduated with honors, and i was in Beta Club for a year and a half.
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Principle's list and A and B honor roll in high school only.
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