Môn Toán Lớp 9 |x1^2-x2^2|=50 Giải hộ ạ
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Athena
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Đáp án+Giải thích các bước giải:
$|x_1^2-x_2^2|=50\\\to (x_1^2-x_2^2)^2=2500(|x_1^2-x_2^2| \geq 0)\\\to x_1^4-2x_1^2.x_2^2+x_2^4=2500\\\to (x_1^2+x_2^2)^2-4(x_1.x_2)^2=2500\\\to [(x_1+x_2)^2-2x_1.x_2]^2-4(x_1.x_2)^2=2500$ Đến đây bạn thay $x_1+x_2,x_1.x_2$ vào nhé!
\( |x_1^2-x_2^2|=50\\↔\sqrt{(x_1^2-x_2^2)^2}=50\\↔\sqrt{x_1^4-2x_1^2x_2^2+x_2^4}=50\\↔\sqrt{(x_1^4+2x_1^2x_2^2+x_2^4)-4x_1^2x_2^2}=50\\↔\sqrt{(x_1^2+x_2^2)^2-4x_1^2x_2^2}=50\\↔\sqrt{[(x_1^2+2x_1x_2+x_2^2)-2x_1x_2]^2-(2x_1x_2)^2}=50\\↔\sqrt{[(x_1+x_2)^2-2x_1x_2]^2-(2x_1x_2)^2}=50\)