#19 I am stuck here: 2cosAsinA+sin^2A+cos^2A=(sinA+cosA)^2
E edgu New member Joined Nov 19, 2009 Messages 2 Nov 19, 2009 #1 #19 I am stuck here: 2cosAsinA+sin^2A+cos^2A=(sinA+cosA)^2
W wjm11 Senior Member Joined Nov 13, 2004 Messages 1,417 Nov 20, 2009 #2 #19 I am stuck here: 2cosAsinA+sin^2A+cos^2A=(sinA+cosA)^2 Click to expand... Just "FOIL" it out: (a + b)^2 = a^2 + 2ab + b^2 (sinA + cosA)^2 = sin^2A + 2cosAsinA + cos^2A
#19 I am stuck here: 2cosAsinA+sin^2A+cos^2A=(sinA+cosA)^2 Click to expand... Just "FOIL" it out: (a + b)^2 = a^2 + 2ab + b^2 (sinA + cosA)^2 = sin^2A + 2cosAsinA + cos^2A
E edgu New member Joined Nov 19, 2009 Messages 2 Nov 20, 2009 #3 Oh ok! Thanks so much, I was trying to simplify the left side instead of the right.
