你好!
数学之美团为你解答
知识点:完全平方公式 (a+b)² = a² + 2ab + b²
x² - kx + 16 = x² - kx + 4²
a = x ,b = 4
∴ - kx = 2ab ,- ka = 8a ,k = - 8
或者 x² - kx + 16 = x² - kx + (-4)²
a = x,b = - 4
∴ - kx = 2ab ,- ka = - 8a ,k = 8
答案:k = ± 8
你好!
数学之美团为你解答
知识点:完全平方公式 (a+b)² = a² + 2ab + b²
x² - kx + 16 = x² - kx + 4²
a = x ,b = 4
∴ - kx = 2ab ,- ka = 8a ,k = - 8
或者 x² - kx + 16 = x² - kx + (-4)²
a = x,b = - 4
∴ - kx = 2ab ,- ka = - 8a ,k = 8
答案:k = ± 8