Example 21 - Chapter 2 Class 11 Relations and Functions

Last updated at August 1, 2026 by

Example 21 - Find domain of f(x) = x2 + 3x + 5 / x2 - 5x + 4

Example 21 - Chapter 2 Class 11 Relations and Functions - Part 2

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Example 21 Find the domain of the function "f" (x) = (" " 2 + 3 + 5)/( 2 5 + 4) "f" (x) = (" " x2 + 3x + 5)/(x2 5x + 4) = (x2 + 3x + 5)/(x2 4x + 4) = (x2 + 3x +5)/( (x 4) 1( 4)) = (x2 + 3x + 5)/(( 4)(x 1) ) In real numbers , the denominator cannot be zero Hence (x 4) (x 1) 0 x 4 and x 1 Hence the domain of the function will be all real numbers except 1 and 4 Hence, the domain = R {1, 4}.

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