RRB
Government Jobs Exams
undefined
if a = root5 +1/root5 -1 and b = root5 -1/root5+1, then value of a2 +ab + b2 /a2 - ab+b2
Read Solution (Total 4)
-
- Given, a= (√5+1)/ (√5-1) = ((√5+1)/ (√5-1))*((√5+1)/ (√5+1)) = (3+√5)/2
And b= (√5-1)/ (√5+1) = ((√5-1)/ (√5+1))*((√5-1)/ (√5-1)) =( 3-√5)/2
(a^2+ab+b^2)/ (a^2-ab+b^2) =((a+b)^2-ab)/ (a+b)^2+ab)= (((3+√5)/2)+(3-√5)/2)^2)-1)/ ((3+√5)/2)+(3-√5)/2)√5)/2)^2)+1)=(9-1)/(3+1)= 8/4=2
ans:- 2 - 8 years agoHelpfull: Yes(2) No(1)
- all answers submitted are wrong till now. this is the correct one.
a= (√5+1)/ (√5-1) = ((√5+1)/ (√5-1))*((√5+1)/ (√5+1)) = (3+√5)/2
And b= (√5-1)/ (√5+1) = ((√5-1)/ (√5+1))*((√5-1)/ (√5-1) =( 3-√5)/2 (a^2+ab+b^2)/ (a^2-ab+b^2) =((a+b)^2-ab)/ (a-b)^2+ab) =(((3+√5)/2)+(3-√5)/2)^2)-1)/ ((3+√5)/2)-(3-√5)/2))^2)+1) =(9-1)/(5+1)=8/6=4/3 - 7 years agoHelpfull: Yes(1) No(0)
- hey m bit confuse in root5-1, 1 is in denominator part or in numerator part?
- 8 years agoHelpfull: Yes(0) No(0)
- iam not getting question please help me
- 8 years agoHelpfull: Yes(0) No(0)
RRB Other Question