Aspire's Library
A Place for Latest Exam wise Questions, Videos, Previous Year Papers,
Study Stuff for MCA Examinations - NIMCET
Study Stuff for MCA Examinations - NIMCET
Previous Year Question (PYQs)
Let A = {1,2,3, ... , 20}. Let $R\subseteq A\times A$ such that R = {(x,y): y = 2x - 7}. Then the number
of elements in R, is equal to
Solution
Given relation: $R = \{(x,y) : y = 2x - 7\}$ where $A = \{1,2,3,\dots,20\}$.
We need both $x, y \in A$.
So, $1 \le y = 2x - 7 \le 20$
⇒ $1 \le 2x - 7 \le 20$
Add 7: $8 \le 2x \le 27$
Divide by 2: $4 \le x \le 13.5$
Hence, integer values of $x$ are $4,5,6,7,8,9,10,11,12,13$ → total $10$ values.
✅ Number of elements in R = 10
Online Test Series, Information About Examination,
Syllabus, Notification
and More.
View More
Online Test Series, Information About Examination,
Syllabus, Notification
and More.
View More
Ask Your Question or Put Your Review.
