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Questions › DSE › DSE 2019 › Q14
0 marksMathematics › Limits, continuity and differentiability › Continuity and discontinuitiesModerateabout 2 min

DSE 2019 Question 14: Limits, continuity and differentiability

It is known that there is a rational number between any two distinct irrational numbers. Consider a continuous function f:ℜ→ℜf:\Re\to\Ref:ℜ→ℜ such that f(x)=sin⁡xf(x)=\sin xf(x)=sinx for every rational number xxx. If xxx is an irrational number, then:

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It is known that there is a rational number between any two distinct irrational numbers. Consider a continuous function f:ℜ→ℜ such that f(x)=sin x for every rational number x. If x is an irrational number, then: (A) f(x)=sin x (B) f(x)=(sin x)/2+(cos x)/2 (C) f(x)=sin (x/2)+cos (x/2) (D) f(x)=cos x

Also written as: It is known that there is a rational number between any two distinct irrational numbers. Consider a continuous function f: Re -> Re such that f(x)=sin x for every rational number x. If x is an irrational number, then:

Limits, continuity and differentiability has come up 122 times in 7 exams since 2006.

What this question tests

This question is on Continuity and discontinuities, part of Limits, continuity and differentiability in Mathematics.

When a function is continuous at a point and what kinds of breaks occur.

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