Elitmus
Exam
Numerical Ability
Arithmetic
Find the sum of roots for---sq root of(x+7)=x. sq root of(x+7)??? asked in e litmus 23rd nov 2014 @Bangaluru
Read Solution (Total 9)
-
- sqrt(x+7)-x*sqrt(x+7)=0
sqrt(x+7)(1-x)=0 => x=-7 or 1
squaring both sides
x+7=x^2*(x+7)=>x^2=1 =>x=+-1
thus the values of x are +1,-1,-7
but if we put -1 the original equation we will get imaginary numbers which cant be compared thus we can say that there will be only 2 solution i.e x=1,-7
so ans is -6 - 10 years agoHelpfull: Yes(18) No(1)
- I think ans will be -7
sq root of (x+7) = x.sq root of (x+7)
squaring both side, we get
=>(x+7) = x^2 (x+7) // In eqn
=> x^2(x+7) - (x+7) = 0
=> (x+7) (x^2 -1) = 0
so roots are= 1,-1,-7
so sum of roots are = -7 - 10 years agoHelpfull: Yes(10) No(15)
- I think ans =0
because as the eqn.....sq root of(x+7)=x. sq root of(x+7)..... is only satisfied by values of x=-1 and +1
So the sum os roots =-1+1=0... - 10 years agoHelpfull: Yes(2) No(3)
- answer will be -6
Reason: sqrt(x+7) {+ve no.} = x. sqrt(x+7){+ve no.} thats mean either x must be +ve or x+7=0
so only x=1 and (x+7 = 0) are possible solution - 10 years agoHelpfull: Yes(1) No(0)
- after simplifying.....
x+7=x2 (x+7)
x2=1
x=+-1
sum of roots=0 - 10 years agoHelpfull: Yes(0) No(2)
- Sq.root(x+7)=x*Sq.root(x+7)
taking squares on both sides
(x+7)=x^2 *(x+7)
(x+7)/(x+7) = x^2
1=x^2
+ or - Sq.root(1)=x
+ or - 1=x - 10 years agoHelpfull: Yes(0) No(3)
- sqr root of(x+7)=x.sqr root of(x+7)
(x+7)=x^2(x+7)
x^2=1
then the result is +1 or -1 - 10 years agoHelpfull: Yes(0) No(2)
- sq root of (x+7) = x.sq root of (x+7)
S.O .B.S
(x+7)=x^2(x+7)
=> x^2=1
=> x=1,-1
sum of roots=1-1
=0 - 10 years agoHelpfull: Yes(0) No(1)
- the two roots are -7 and 1 so there sum is -6
- 9 years agoHelpfull: Yes(0) No(0)
Elitmus Other Question