等式x ^ 2 -4x-8 = 0具有5到6之间的解。找到该等式的解到小数点后1位。我该怎么做呢?
X = 5.5或-1.5使用x = [ - b pmsqrt(b ^ 2-4xxaxxc)] /(2a)其中a = 1,b = -4且c = -8 x = [4 pmsqrt(( - 4) )^ 2-4xx1xx-8)] /(2xx1)x = [4 pmsqrt(16 + 32)] /(2)x = [4 pmsqrt(48)] /(2)x = [4 pm4sqrt( 3)] /(2)x = 2 + 2sqrt3或x = 2-2sqrt3 x = 5.464101615或x = -1.464101615
Y-4 = 3(x- 2)以斜率截距形式写出方程。我该怎么做呢?
Y = 3x - 2是斜率截距形式,斜率= 3,y截距= -2 y - 4 = 3(x- 2)y = 3x - 6 + 4 y = 3x - 2是斜率截距形式斜率= 3,y轴截距= -2