W wolf7 Member Joined Oct 10, 2005 Messages 49 Gender Male HSC 2006 Oct 22, 2005 #1 how does this equation work a^2+b^2=(a+b)^2-2ab is there some technique getting there or is it just is
how does this equation work a^2+b^2=(a+b)^2-2ab is there some technique getting there or is it just is
M Mystic Crusader New Member Joined Mar 20, 2005 Messages 5 Gender Male HSC 2006 Oct 22, 2005 #2 quadratic a^2 + b^2 =(a+b)^2 -2ab RHS = (a+b)^2 -2ab = a^2 + 2ab +b^2 -2ab by expanding the brackets =a^2+ b^2 collecting like terms =LHS i hope this helps you =)
quadratic a^2 + b^2 =(a+b)^2 -2ab RHS = (a+b)^2 -2ab = a^2 + 2ab +b^2 -2ab by expanding the brackets =a^2+ b^2 collecting like terms =LHS i hope this helps you =)
W wolf7 Member Joined Oct 10, 2005 Messages 49 Gender Male HSC 2006 Oct 22, 2005 #3 thanx people, i understand how to use it
I icycloud Guest Oct 22, 2005 #4 Just a note: this can be expanded for a4 + b4, a6 + b6, an + bn where n is an even number. As such: a4 + b4 = (a2)2 + (b2)2 = (a2 + b2)2 - (√2 ab)2 = (a2 + b2 - √2 ab)(a2 + b2 + √2 ab) This sort of manipulation might come in handy, if not in 2U then in 3U or 4U.
Just a note: this can be expanded for a4 + b4, a6 + b6, an + bn where n is an even number. As such: a4 + b4 = (a2)2 + (b2)2 = (a2 + b2)2 - (√2 ab)2 = (a2 + b2 - √2 ab)(a2 + b2 + √2 ab) This sort of manipulation might come in handy, if not in 2U then in 3U or 4U.
