WBBSE 9th Class Math Solutions Chapter 21 লগারিদম
WBBSE 9th Class Math Solutions Chapter 21 লগারিদম
West Bengal Board 9th Class Math Solutions Chapter 21 লগারিদম
West Bengal Board 9th Math Solutions
কযে দেখি 21
1. মান নির্ণয় করি :
![](https://i0.wp.com/sabdekho.in/wp-content/uploads/2023/11/20231106_110431785.jpg?resize=288%2C381&ssl=1)
2. (a) 625-এর লগারিদম 4 হলে নিধান কি হবে হিসাব করে লিখি।
Ans. মনেকরি নিধান x
∴ logx625 = 4
বা, x4 = 625
বা, x4 = 25 × 25
বা, x4 = 54
বা, x = 5
∴ নিধান হবে 5
(b) 5832-এর লগারিদম 6 হলে নিধান কী হবে হিসাব করে লিখি।
Ans. মনেকরি নিধান x
∴ logx5832 = 6
বা, x6 = 5832
বা, x6 = (3√2)6
বা, x = 3√2
∴ নিধান হবে 3√2
3. (a) 1 + log10a = 2 log10b হলে a কে b-এর দ্বারা প্রকাশ করি।
Ans. 1 + log10a = 2 log10b
বা, 1 = log10b2 – log10a
![](https://i0.wp.com/sabdekho.in/wp-content/uploads/2023/11/20231106_110431785-1.jpg?resize=360%2C437&ssl=1)
4. মান নির্ণয় করো :
(a) log2 [log2 {log3 (log3273)}]
![](https://i0.wp.com/sabdekho.in/wp-content/uploads/2023/11/20231106_110431785-2.jpg?resize=288%2C499&ssl=1)
![](https://i0.wp.com/sabdekho.in/wp-content/uploads/2023/11/20231106_110603043.jpg?resize=720%2C377&ssl=1)
5. প্রমাণ করি :
![](https://i0.wp.com/sabdekho.in/wp-content/uploads/2023/11/20231106_110603043-1.jpg?resize=792%2C707&ssl=1)
![](https://i0.wp.com/sabdekho.in/wp-content/uploads/2023/11/20231106_110802910.jpg?resize=655%2C1024&ssl=1)
![](https://i0.wp.com/sabdekho.in/wp-content/uploads/2023/11/20231106_110909862.jpg?resize=792%2C214&ssl=1)
![](https://i0.wp.com/sabdekho.in/wp-content/uploads/2023/11/20231106_110909862-1.jpg?resize=720%2C729&ssl=1)
![](https://i0.wp.com/sabdekho.in/wp-content/uploads/2023/11/20231106_110909862-2.jpg?resize=576%2C112&ssl=1)
![](https://i0.wp.com/sabdekho.in/wp-content/uploads/2023/11/20231106_111016403.jpg?resize=504%2C228&ssl=1)
![](https://i0.wp.com/sabdekho.in/wp-content/uploads/2023/11/20231106_111016403-1.jpg?resize=792%2C856&ssl=1)
![](https://i0.wp.com/sabdekho.in/wp-content/uploads/2023/11/20231106_111138768.jpg?resize=576%2C440&ssl=1)
10. সমাধান করি :
![](https://i0.wp.com/sabdekho.in/wp-content/uploads/2023/11/20231106_111138768-1.jpg?resize=324%2C555&ssl=1)
![](https://i0.wp.com/sabdekho.in/wp-content/uploads/2023/11/20231106_111138768-2.jpg?resize=288%2C145&ssl=1)
![](https://i0.wp.com/sabdekho.in/wp-content/uploads/2023/11/20231106_111138768-3.jpg?resize=576%2C560&ssl=1)