If a + b = 1, c + d = 1 and a – b =d , then the value

Home » Aptitude » Algebra » Question

d	= a − b
c

⇒	c	=	1	=	a + b
	d		a − b		a − b

⇒	c + d	=	a + b + a − b	=	a
	c − d		a + b − a + b		b

(By componendo and dividendo)

⇒	1	=	a
	c − d		b

⇒ (c – d) =	b
	a

⇒ c² – d² = (c + d) (c – d) =	b
	a

If a + b = 1, c + d = 1 and a – b =	d	, then the value of c² − d² is
	c