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16 ^ x - 3 * 2 ^ (2x) + 2 = 0 find value of x​

User Ryebread
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Answer:

To solve for x in the equation 16^x - 3 2^(2x) + 2 = 0, we can apply logarithms to both sides of the equation. One option is to use the natural logarithm (ln) because it helps simplify the equation:

16^x - 3 2^(2x) + 2 = 0

16^x + 2 = 3 2^(2x)

ln(16^x + 2) = ln(3 2^(2x))

ln(16^x + 2) = ln(3) + ln(2^(2x))

ln(16^x + 2) = ln(3) + 2x ln(2)

ln(16^x + 2) - 2x ln(2) = ln(3)

Now we can solve for x using numerical or graphical methods, since there is no algebraic solution for x. One possible way is to use Newton's method of approximation, which involves iterating the formula:

xn+1 = xn - f(xn) / f'(xn)

where xn is an approximation of x, f(x) is the function we want to solve for, and f'(x) is its derivative. In this case,

f(x) = 16^x + 2 - 3 2^(2x)

f'(x) = 16^x ln(16) - 12 2^(2x) ln(2)

We can start the iteration with an initial guess of x0 = 1, for example:

x1 = x0 - f(x0) / f'(x0)

= 1 - (16^1 + 2 - 3 2^(21)) / (16^1 ln(16) - 12 2^(21) ln(2))

= 0.545

x2 = x1 - f(x1) / f'(x1)

= 0.545 - (16^0.545 + 2 - 3 2^(20.545)) / (16^0.545 ln(16) - 12 2^(2*0.545) * ln(2))

= 0.678

x3 = x2 - f(x2) / f'(x2)

= 0.678 - (16^0.678 + 2 - 3 2^(20.678)) / (16^0.678 ln(16) - 12 2^(2*0.678) * ln(2))

= 0.736

x4 = x3 - f(x3) / f'(x3)

= 0.736 - (16^0.736 + 2 - 3 2^(20.736)) / (16^0.736 ln(16) - 12 2^(2*0.736) * ln(2))

= 0.764

x5 = x4 - f(x4) / f'(x4)

= 0.764 - (16^0.764 + 2 - 3 2^(20.764)) / (16^0.764 ln(16) - 12 2^(2*0.764) * ln(2))

= 0.779

We can continue the iterations until the desired level of accuracy is reached, for example, when |x5 - x4| < 0.001. In this case, the approximate solution for x is x ≈ 0.779.

User Hoodlum
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