SSC Selection Post 2024 PYQ — Question 54

SSC Selection Post - Higher Secondary Level - 24 June 2024 - Shift 2 • Quantitative Aptitude • Q54

If x2+y2+z2=xy+yz+zx,x^2+ y^2+ z^2 = xy+yz+zx, then the value of (17x4+9y4+16x48x2y2+6y2z2+10z2x2)\left (\frac{17x^4+9y^4+16x^4}{8x^2y^2+6y^2z^2+10z^2x^2}\right ) is:

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Correct answer: D

Explanation

The correct answer is Option 4 i.e. 1.75.

x2+y2+z2=xy+yz+zxx^2+ y^2+ z^2 = xy+yz+zx

x2 + y2 + z2 - xy - yz - zx = 0 

⇒ 121\over2[(x - y)2 + (y - z)2 + (z - x)2] = 0

⇒ x = y = z

(17x4+9y4+16x48x2y2+6y2z2+10z2x2)\left (\frac{17x^4+9y^4+16x^4}{8x^2y^2+6y^2z^2+10z^2x^2}\right ) = (17+9+16)x4(8+6+10)x4\frac{(17+9+16)x^4}{(8+6+10)x^4}  = 422442\over24 = 747\over4 = 1.75