What is 8+6|6-4x|=20?
回答 (2)
2016-06-30 7:57 pm
8 + 6 |6 - 4x| = 20
6 |6 - 4x| = 12
|6 - 4x| = 2
6 - 4x = 2 or 6 - 4x = -2
-4x = -4 or -4x = -8
x = 1 or x = 2
6 |6 - 4x| = 12
|6 - 4x| = 2
6 - 4x = 2 or 6 - 4x = -2
-4x = -4 or -4x = -8
x = 1 or x = 2
2016-06-30 8:35 pm
If x = a + bi, where a and b are real numbers and i^2 = -1, we have:
|6 - 4(a + bi)| = 2
|(6 - 4a) - 4bi| = 2
sqrt((6 - 4a)^2 + (-4b)^2) = 2
(6 - 4a)^2 + (-4b)^2 = 2^2
36 - 48a + 16a^2 + 16b^2 = 4
16a^2 - 48a + 16b^2 + 36 - 4 = 0
16a^2 - 48a + 16b^2 + 32 = 0
There are infinity solutions (if x can be non-real).
|6 - 4(a + bi)| = 2
|(6 - 4a) - 4bi| = 2
sqrt((6 - 4a)^2 + (-4b)^2) = 2
(6 - 4a)^2 + (-4b)^2 = 2^2
36 - 48a + 16a^2 + 16b^2 = 4
16a^2 - 48a + 16b^2 + 36 - 4 = 0
16a^2 - 48a + 16b^2 + 32 = 0
There are infinity solutions (if x can be non-real).
收錄日期: 2021-04-18 15:15:46
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