3. Solve for x:=-+-+-. a + b +x0, a, b, x0.a+b+x a b x4.+EM.3Solve for

1.	3. Solve for x:=-+-+-. a + b +x0, a, b, x0.a+b+x a b x4.+EM.3Solve for x:
Answer» 3)1/a+b+x = 1/a + 1/b + 1/c 1/a+b+x = bx+ax+ab/abx abx = 3abx + a2x +b2x + a2b+ab2 x2 ( a+b) + x( a2 + b2 +2ab ) + ab( a+b) =0 x2 ( a+b) + x(a+b)2 + a2b+ ab2 = 0 D = b2 - 4ac = (a+b)4 - 4 ( a+b) ( a2b+ab2 ) = a4 + b4 + 4a3b + 4ab3 + 6a2b2 - 4a3b - 4ab3 - 8a2b2 = a4 + b4 - 2a2b2 = (a2 - b2)2 x = -(a+b)2 (+or -) root of (a2-b2)2 / 2(a+b) = -a2 - b2 -2ab +a2 -b2/a(a+b) = -2b2 - 2ab/2(a+b) = -2b(a+b)/2(a+b) = -b similarly the other root is -a

3. Solve for x:=-+-+-. a + b +x0, a, b, x0.a+b+x a b x4.+EM.3Solve for x:

Answer»

3)1/a+b+x = 1/a + 1/b + 1/c

1/a+b+x = bx+ax+ab/abx

abx = 3abx + a2x +b2x + a2b+ab2

x2 ( a+b) + x( a2 + b2 +2ab ) + ab( a+b) =0

x2 ( a+b) + x(a+b)2 + a2b+ ab2 = 0

D = b2 - 4ac

= (a+b)4 - 4 ( a+b) ( a2b+ab2 )

= a4 + b4 + 4a3b + 4ab3 + 6a2b2 - 4a3b - 4ab3 - 8a2b2

= a4 + b4 - 2a2b2

= (a2 - b2)2

x = -(a+b)2 (+or -) root of (a2-b2)2 / 2(a+b)

= -a2 - b2 -2ab +a2 -b2/a(a+b)

= -2b2 - 2ab/2(a+b)

= -2b(a+b)/2(a+b)

= -b

similarly the other root is -a