easy...

if the expression 16x⁴ - 24x³ +41x² â€“ nx +16 is a perfect square then the value of â€˜nâ€™ is.

2 Answers

106

Asish Mahapatra ·2011-02-10 10:08:20

we have (ax^2 + bx + c)² = 16x⁴ - 24x³ + 41x² - nx + 16
now its just comparing coefficients

a² = 16 ... (1)
c² = 16 ... (2)
2ab = -24 ... (3)
b² + 2ac = 41 ... (4)

u can get value of a,b,c from these

and n = -2bc

@Ashish -> wonderful...!!

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