✔ 最佳答案
只要碳酸氫鹽和酸不太稀或不太少量,碳酸氫鹽和酸*設A、B兩多項式的次數分別為4次,2次,則f(x)*g(x)的次數為 ?
若 A = f(x) 及 B = g(x),
f(x) 的最高次項為 x^4 項,而 g(x) 的最高次項為 x^2 項。
f(x)*g(x) 的最高之最高次項為 x^4 * x^2 = x^6
f(x)*g(x) 的次數 = 6
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*若(x+1)(2x+3)-10=2(x-a)(x-b),則(a+1)(b+1)=?
令x = -1,
(x + 1)(2x + 3) - 10 = 2(x - a)(x - b)
(-1 + 1)(2(-1) + 3) - 10 = 2(-1 - a)(-1 - b)
0 - 10 = 2[-(1 + a)][-(1 + b)]
2(a + 1)(b + 1) = -10
(a + 1)(b + 1) = -5
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*因式分解(a - 2)^2 - 3(2 - a) = (a - 2) * X,X=?
(a - 2)^2 - 3(2 - a)
= (a - 2)[(a - 2) - 3]
= (a - 2)(a - 5)
所以 X = a - 5
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*因式分解bx^2-b+x-b^2x=?
bx^2-b+x-b^2x
= (bx^2 - b^2x) + (x - b)
= bx(x - b) + (x - b)
= (x - b)(bx + 1)
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*一平年中,月份用x表示,當月的天數用y表示,若f(x)=y,f(2)=?
f(2) = 28
(平年二月份有 28 日)
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*設函數f(x)=2,f(2)+f(-2)的值等於?
f(2) = 2
f(-2) = 2
f(2) + f(-2)
= 2 + 2
= 4
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*設f(x-2)=x^2-3x+2,則f(1)=?
令 u = x - 2,則 x = u + 2
f(u) = (u + 2)^2 - 3(u + 2) + 2
f(1)
= (1 + 2)^2 - 3(1 + 2) + 2
= 9 - 9 + 2
= 2