For all integers n
n* = n(n-1) WHat is the value of x*
1>x* = x(x-1)
2>(x-1)* = x-2
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please help ...OA needed urgently
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Gmatss
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IMO B
Stament one just repeats it self and values of x will vary
Statement 2 says (x-1)*=x-2
which implies (x-1)*= (x-1)((x-1)-1) =>
(X-1)(x-2)=(x-2)=> x^2-3x+2=x-2 and from here it's just solving quad equations. so hence B answer should be x=2
Stament one just repeats it self and values of x will vary
Statement 2 says (x-1)*=x-2
which implies (x-1)*= (x-1)((x-1)-1) =>
(X-1)(x-2)=(x-2)=> x^2-3x+2=x-2 and from here it's just solving quad equations. so hence B answer should be x=2
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raju232007
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n*=n(n-1) .......Given
statement 1:
x*=x(x-1)
x(x-1)=x(x-1)
x can have number of values and hence this statement is insufficient
statement 2:
(x-1)*=(x-2)
(x-1)(x-2)=(x-2) ( applying the formula given in the question stem)
x-1=1
x=2
2*=2(2-1)=2
Statement 2 is sufficient
Hence the OA should be B....
statement 1:
x*=x(x-1)
x(x-1)=x(x-1)
x can have number of values and hence this statement is insufficient
statement 2:
(x-1)*=(x-2)
(x-1)(x-2)=(x-2) ( applying the formula given in the question stem)
x-1=1
x=2
2*=2(2-1)=2
Statement 2 is sufficient
Hence the OA should be B....
