sina*cosa=4/7 , a=?

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- Oct 29th 2008, 12:59 PMi.s.tzortzissina*cosa=4/7 , a=?
sina*cosa=4/7 , a=?

- Oct 29th 2008, 01:42 PMskeeter

there is no solution for "a" to satisfy this equation ... why? - Feb 2nd 2010, 10:54 PMafsanehanswer
sin2a<1 then 2sina.cosa<1 so sina.cosa<1/2

4/7 is not less than 1/2 and equation is not true. - Feb 2nd 2010, 11:50 PMpacmansin 2A
see the graph . . . . no roots possible; sin A cos A = 4/7. The red and blue wont meet . . . .

http://www1.wolframalpha.com/Calcula...image/gif&s=43

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