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प्रश्न
Find x.
5x + 5x – 1 = 750
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उत्तर
We have, 5x + 5x – 1 = 750
⇒ `5^x + 5^x/5 = 750` ...`[∵ a^-m = 1/a^m]`
⇒ `5^x (1 + 1/5) = 750`
⇒ `5^x (6/5) = 750`
⇒ `5^x = 750 xx 5/6`
⇒ 5x = 125 × 5
⇒ 5x = 625
⇒ 5x = 54
On comparing the power of 5, we get
x = 4
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Amount (in Rs) |
| 1st square | 1 |
| 2nd square | 2 |
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If a = – 1, b = 2, then find the value of the following:
ab × ba
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