Question

Решите уравнение

а) (x+1)2-(2x-1)2=0

б) (4x+3)2-(3x-1)2=0

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Answer 1

$(4x+3)^{2}-(3x-1)^{2}=0\\16x^{2}+24x+9-9x^{2}+6x-1=0\\5x^{2}+30x+8=0\\D=900-4*5*8=740\\x1=(-30-\sqrt{740} ) /10=-3-0.2\sqrt{185}\\x2=(-30+ \sqrt{740}) /10 =-3+2\sqrt{185}$

$(x+1)^{2}-(2x-1)^{2}=0\\x^{2} +2x+1-4x^{2}+4x-1=0\\-3x^{2} +6x=0\\x^{2} -2x=0\\D=4\\x1=0\\x2=2$