Yahoo奇摩 網頁搜尋

  1. 6. (√5-√2)(√3-1)= A. 2√5-2√2 B. √15-√5-2√2 C. 2√5-√6+√2 D. √15-√6-√5+√2 (√5-√2)(√3-1) = √5√3-√5-√2√3+√2 = √15-√6-√5+√2 (Answer D) ================================================ 7. (√6-√5)² = A. 1-√30 B. 1-2√30...

  2. The factor of polynomials must have x+5 Let f(x) = x^3+ax^2+bx+5 f(-5) = 0 (-5)^3+a(-5)^2+b(-5)+5 = 0 -125+25a-5b+5 = 0 25a-5b = 120 5a-b = 24 ---(1) Let g(x) = x^2+(b-a)x-5 g(-5) = 0 (-5)^2 + (b-a)(-5) - 5 = 0 25 -5(b-a) - 5 = 0 b-a = 4 b = a+4 ---(2) Put (2) into (1), 5a - (a+4) = 24 4a - 4 = 24 4a = 28 a = 7...

    分類:科學及數學 > 數學 2010年03月28日

  3. 1) find the H.C.F. and L.C.M. of xyz^3 ,x^2yz and y^2z Sol yz|xyz3,x2yz,y2z   ──────────────     xz2,  x2,  y H.C...

    分類:科學及數學 > 數學 2013年02月09日

  4. 1) {x^(1/2)/[x^(1/3)]}x^(1/4) = x^(1/2 - 1/3 + 1/4) = x^[(6 - 4 + 3)/12] = x^(5/12) 2) {[x^(3n)/(y^5)]^(1/2)}[(x^n)/(y^3)]^(1/2) = x^(3n/2 + n/2) / y^(5/2 + 3/2) = x^(2n)/(y^4) 3) (1 , 3) , (2 , 5) , (3 , 7) , (4 , 9) , (5 , 11) i.e. (n , 2n + 1) where n = 1, 2, 3, 4, 5 i.e. They are collinear on y = 2x + 1.

    分類:科學及數學 > 數學 2012年12月19日

  5. √=開方` 1. Given √5=2.23607, correct to 5 decimal places. Find the value of 1/√5 correct to 3 decimal places. A. 1/√5 = 1/√5 * √5/√5----------------rationalization(有理化) = √5/(√5*√5) = √5/5----------√5*√5 = √5^2 = 5 = 0.447(cor. to 3 sig. fig.) 2. Given...

  6. 1/(6-2x)+2/(2x+6) = -1 / (2x - 6) + 2 / (2x + 6) = [-1 (2x + 6) + 2 (2x - 6)] / [(2x + 6)(2x - 6)] = (-2x - 6 + 4x - 12) / (4x^2 - 36) = (2x - 18) / (4x^2 - 36) = (x - 9) / [2(x^2 - 9)] [(3x^2-8x+4/x-2)-(x+6/3x-2)](9x^2-12x+4/9x^2-13x-2) = [(3x - 2) (x - 2) / (x - 2) - (x + 6) / (3x - 2)] x [(9x^2-12x+4) / (9x^2-13x-2)] = [(3x - 2)^2 / (3x - 2) - (x + 6) / (3x - 2)] x...

    分類:科學及數學 > 數學 2010年04月05日

  7. 1) Find the HCF and LCM of x+3, x^2-9 and x^3+27 x+3 , x^2 - 3^2 and x^3 + 3^3 x+3 , (x-3)(x+3) and (x+3)(x^2 - 3x + 9) HCF = x+3 LCM = (x+3)(x-3)(x^2 - 3x + 9) 2)Simplify (1/4x+1 - 1/1-4x) / (4x^2+2x / 4x^2 + 7x -2) = [(1-4x) - (4x+1)] / (4x+1)(1-4x)] / (4x^2+2x / 4x^2 + 7x -2) = [- 8x / (4x+1...

    分類:科學及數學 > 數學 2010年03月30日

  8. no. it is not possible for the company to remove 100% of the pollutants. it is because the cost will be very high. C=80000p/(100-p) when p=100, 100-100=0 so the fraction will become C=8000000/0 C=infinity. the company will be at totally loss. it is because it will be much expense for the...

    分類:科學及數學 > 數學 2008年04月29日

  9. 開方10 =開方(9+1)> 3 but < 4 開方50 =開方(49+1)>7 but < 8 lie between 開方10 and 開方50 i.e 3<X<8, therefore X can be 4, 5, 6, or 7 assume only use positive integer here.

    分類:科學及數學 > 數學 2008年09月06日

  10. 1. 64x³ + 1 = (4x + 1)(16x² -4x + 1) 16x² + 8x + 1 = (4x + 1)² 16x² - 1 = (4x + 1)(4x - 1) G.C.D. = 4x + 1 L.C.M. = (4x + 1)²(4x - 1)( 16x² -4x + 1) ==== 2. 6x² + 7x - 3 = (3x - 1)(2x + 3) 3x² + 5x - 2...

    分類:科學及數學 > 數學 2015年02月02日