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2 years ago

Find the sum of the digits 10^15−1.

Mathematics

2 answers:

Shtirlitz [24]2 years ago

8 0

Answer:

135

Step-by-step explanation:

10^15 = 1 000 000 000 000 000

10^15 - 1 = 999 999 999 999 999

There are 15 nines

15*9 = 135

Alchen [17]2 years ago

4 0

Answer:

149

Step-by-step explanation:

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$\frac{ax^2}{a} + \frac{bx}{c} + \frac{c}{a} =0$
$x^{2} + \frac{b}{a} x+ \frac{c}{a} =0$

Step 3. Subtract $\frac{c}{a}$ from both sides of the equation:
$x^{2} + \frac{b}{a} x+ \frac{c}{a}- \frac{c}{a} =0 - \frac{c}{a}$
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Step 4. Complete the square of the left hand side by adding $( \frac{b}{2a} )^2$ to both sides:
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Step 5. Take square root to both sides of the equation:
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