`M = x^2 + y^2 - x + 6y + 10`
`M = x^2 - x + y^2 + 6y + 10`
`M = x^2 - 2 . x . 1/2 + 1/4 + y^2 + 2 . y . 3 + 9 + 3/4 `
`M = (x - 1/2)^2 + (y + 3)^2 + 3/4 `
`Do (x - 1/2)^2 + (y + 3)^2 ≥ 0`
`⇒ M ≥ 0 + 3/4 = 3/4`
`text(Min)` `M = 3/4 khi x = 1/2 ; y = -3`
Đáp án:
`min_M=3/4<=>x=1/2,y=-3`
Giải thích các bước giải:
`M=x^2+y^2-x+6y+10`
`<=>4M=4x^2+4y^2-4x+24y+40`
`<=>4M=4x^2-4x+1+4y^2+24y+36+3`
`<=>4M=(2x-1)^2+(2y+6)^2+3`
VÌ `(2x-1)^2+(2y+6)^2>=0`
`=>4M>=3=>M>=3/4`
Dấu "=" xảy ra khi `{(2x-1=0),(2y+6=0):}<=>x=1/2,y=-3`
Vậy `min_M=3/4<=>x=1/2,y=-3`
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Vẽ mihawk ngầu, đẹp cho hay nhất và ghi tên bên góc phải là ★и★ѕ★мιнαωк★. Xấu bc nha!
rewrite sentences 1:suán and tom have been maried for 5 years =) It's ..
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Cho $\frac{x}{2}$ = $\frac{y}{5}$ = $\frac{z}{7}$ . Tính giá trị biểu thức A=$\frac{x-y+z}{x+2y-z}$ Nhanh nha mn
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