Positive Values of $a$, $b$, $c$, and $d$ for Log Inequality

In summary, to find the positive values of $a,\,b,\,c,$ and $d$ that satisfy the given inequalities, we can use the properties of logarithms to rewrite them as a system of three simpler inequalities. By setting $b = 1,\,c = 2,\,d = 3,$ and any positive value for $a$ greater than 2, we can determine the values that satisfy the original inequalities.
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Determine the positive values of $a,\,b,\,c$ and $d$ such that $\log_{d+3} (a + 3)>\log_{c+2} (d + 2)>\log_{b+1} (c + 1) >\log_a (b)$.
 
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To solve this problem, we can use the properties of logarithms to rewrite the inequalities in a more manageable way. First, let's rewrite the first inequality as a logarithm equation:

$\log_{d+3} (a + 3) > \log_{c+2} (d + 2)$

Using the property $\log_a (b) > \log_a (c)$ if $b > c$, we can rewrite this as:

$a + 3 > d + 2$

Similarly, we can rewrite the second inequality as:

$d + 2 > c + 1$

And the third inequality as:

$c + 1 > b$

Now we have a system of three inequalities:

$a + 3 > d + 2$

$d + 2 > c + 1$

$c + 1 > b$

To solve this system, we can start by setting $b = 1$ since we know that the logarithm of 1 is always 0. This simplifies the third inequality to:

$c > 0$

Next, we can set $c = 2$ to simplify the second inequality to:

$d > 1$

Finally, we can set $d = 3$ to simplify the first inequality to:

$a > 2$

Therefore, the values of $a,\,b,\,c,$ and $d$ that satisfy the given inequalities are:

$a > 2,\, b = 1,\, c > 0,\, d > 1$

In other words, any positive values for $a,\,c,$ and $d$ that are greater than 2, 0, and 1 respectively, and any value for $b$ that is equal to 1, will satisfy the given inequalities.
 

FAQ: Positive Values of $a$, $b$, $c$, and $d$ for Log Inequality

"What is the significance of positive values for a, b, c, and d in log inequalities?"

Positive values for a, b, c, and d in log inequalities indicate that the inequality is true for all values of the variables. This means that the inequality holds for all positive numbers, since logarithms are only defined for positive numbers. It also means that the graph of the inequality will always be above the x-axis, as log functions are always positive for positive inputs.

"Can negative values for a, b, c, and d in log inequalities be ignored?"

No, negative values for a, b, c, and d in log inequalities cannot be ignored. These values can significantly impact the behavior of the inequality and must be taken into consideration when solving or graphing the inequality. For example, a negative value for a would result in a reflection of the graph over the x-axis.

"How can we determine the range of values for a, b, c, and d in a log inequality?"

The range of values for a, b, c, and d in a log inequality can be determined by considering the behavior of the inequality for different values of the variables. For example, if the inequality involves a log function with a base greater than 1, the range of values for a would be all positive real numbers. Similarly, if the inequality involves a log function with a base between 0 and 1, the range of values for a would be all negative real numbers.

"What is the role of a in log inequalities?"

The value of a in log inequalities determines the vertical stretch or compression of the graph. A larger value of a would result in a steeper graph, while a smaller value of a would result in a flatter graph. Additionally, a negative value for a would result in a reflection of the graph over the x-axis.

"Are there any restrictions on the values of b, c, and d in log inequalities?"

Yes, there are some restrictions on the values of b, c, and d in log inequalities. The base of the logarithm (b) must be a positive real number, and the input of the log function (c) must be a positive real number. Additionally, d must be a real number, but it does not have any restrictions on its sign.

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