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The number of real roots of the equation x⁴+ x⁴+20 =22 is

Options

  1. A4
  2. B2
  3. C0
  4. D1

Correct answer

B. 2

Step-by-step solution

Given, x⁴+ x⁴+20 =22 Add both sides 20, we get x⁴+20+ x⁴+20 =22+20 Let x⁴+20 =y y²+y-42=0 (y-6)(y+7)=0 y=6 [y -7] x⁴+20 =6 x⁴+20=36 x⁴=16 x= 2 Hence, the number of real roots of the equation is 2 .

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