please answer the question given below
...if the answer is correct then you'll be marked as brainliest....at least try...BTW the answer is 12 but I need the whole solution....pls
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Hey !
Step-by-step explanation:
Given : 2019^x+2019^-x=3
To Find : value of
12019^6x-2019^-x=2019^x-2019^-X
2019^x+2019^-x=3
Let say 2019^x = a
=> 2019^-x = 1/a
a + 1/a = 3
=> a² + 1 = 3a
(√2019^6x-2019^-x)÷ (2019^x-2019^-x)
= (2019^3x - 2019^-x)÷ (2019^x-2019^-x)
= ( a³ - 1/a) ÷ (a -1/a)
multiplying numerator and denominator by a
= ( a⁴ - 1) ÷ (a² - 1)
= (a² + 1)(a² - 1) ÷ (a² - 1)
= a² + 1
= 3a
a² + 1 = 3a
=> a² - 3a + 1 = 0
=> a = (3 ± √9-4)/2
=> a = (3 ± √5)/2
√2019^6x-2019^-x÷2019^x-2019^-x = 3 (3 ± √5)/2
I Hope it helps You ❤
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