Example Solve the octic polynomial 2x⁸-9x⁷+20x⁶-33x⁵+46x⁴-66x³+80x²-72x+32=0 Solution Divide by x⁴ 2x⁴-9x³+20x²-33x+46-66/x + 80/x² - 72/x³ + 32/x⁴=0 Combine and bring terms 2(x⁴+16/x⁴) - 9(x³+8/x³) +20(x²+4/x²)-33(x+2/x) + 46= 0 Let use substitution Let x+2/x =u (x+2/x)²= u² x²+2x*2/x + 4/x² = u² x²+4/x²= u²-4 (x+2/x)³= x³+8/x³+3x*2/x(x+2/x) u³= x³+8/x²+6u x³+8/x³= u³-6u (x²+4/x²)²= x⁴+2x²*4/x² + 16/x⁴ (u²-4)²= x⁴+16/x⁴ + 8 x⁴+16/x⁴ = (u²-4)²-8 x⁴+16/x⁴ = u⁴-8u²+8 2(u⁴-8u²+8)-9(u³-6u)+20(u²-4)-33u+46=0 Expand and simplify 2u⁴-9u³+4u²+21u-18=0 After checking (u-1)(u-2) Are factors Then 2u²-3u-9=0 u=3, u=-3/2 Assignment question Solve the octic polynomial 2s⁸+s⁷+2s⁶-31s⁴-16s³-32s²-160=0 using the above example question, please explain in detail

Example Solve the octic polynomial 2x⁸-9x⁷+20x⁶-33x⁵+46x⁴-66x³+80x²-72x+32=0 Solution Divide by x⁴ 2x⁴-9x³+20x²-33x+46-66/x + 80/x² - 72/x³ + 32/x⁴=0 Combine and bring terms 2(x⁴+16/x⁴) - 9(x³+8/x³) +20(x²+4/x²)-33(x+2/x) + 46= 0 Let use substitution Let x+2/x =u (x+2/x)²= u² x²+2x2/x + 4/x² = u² x²+4/x²= u²-4 (x+2/x)³= x³+8/x³+3x2/x(x+2/x) u³= x³+8/x²+6u x³+8/x³= u³-6u (x²+4/x²)²= x⁴+2x²*4/x² + 16/x⁴ (u²-4)²= x⁴+16/x⁴ + 8 x⁴+16/x⁴ = (u²-4)²-8 x⁴+16/x⁴ = u⁴-8u²+8 2(u⁴-8u²+8)-9(u³-6u)+20(u²-4)-33u+46=0 Expand and simplify 2u⁴-9u³+4u²+21u-18=0 After checking (u-1)(u-2) Are factors Then 2u²-3u-9=0 u=3, u=-3/2 Assignment question Solve the octic polynomial 2s⁸+s⁷+2s⁶-31s⁴-16s³-32s²-160=0 using the above example question, please explain in detail

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter6: Power Flows

Section: Chapter Questions

Problem 6.39P

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