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# Solve for x :S watch

1. Solve for x:

Where do I even start? :s Bases are different.

I tried exponentiating both sides (raising both sides to the power of x and then also tried the same but to the power of 8, also tried expressing the whole expression in terms of e, rather than 8. Got somewhere but nowhere useful, I believe.

Thanks!

Sid
2. (Original post by Sidhant Shivram)
...
Can't see the image.

Guessing - you're going to need to change the base.
3. (Original post by Sidhant Shivram)
Solve for x:

Where do I even start? :s Bases are different.

I tried exponentiating both sides (raising both sides to the power of x and then also tried the same but to the power of 8, also tried expressing the whole expression in terms of e, rather than 8. Got somewhere but nowhere useful, I believe.

Thanks!

Sid
As ghostwalker said, the picture isn't there. However, it may be useful to remember that .
4. (Original post by ghostwalker)
Can't see the image.

Guessing - you're going to need to change the base.
(Original post by Smaug123)
As ghostwalker said, the picture isn't there. However, it may be useful to remember that .

18.b) The 2nd part
Attached Images

5. (Original post by Sidhant Shivram)

18.b) The 2nd part
unless or . That's how I'd end up doing it, I think.
6. (Original post by Smaug123)
unless or . That's how I'd end up doing it, I think.

Ah yes. Makes sense. I used your method. Got some sensible answers. However, the answers given are : 4 and 16 x root2 :/

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7. you can write the 2 on its own as 2log33
8. (Original post by the bear)
you can write the 2 on its own as 2log33
Exactly the same as what I was thinking.
May be better to write it as the logarithm of 9 to base 3 however.
9. (Original post by the bear)
you can write the 2 on its own as 2log33
(Original post by MathMeister)
Exactly the same as what I was thinking.
May be better to write it as the logarithm of 9 to base 3 however.
The first part is fine. its the 2nd part, part (b), i.e., thats bothering me.
10. (Original post by Sidhant Shivram)
The first part is fine. its the 2nd part, part (b), i.e., thats bothering me.
Change of base rule.
11. (Original post by Smaug123)
.
this is easier
12. (Original post by MathMeister)
Change of base rule.
(Original post by the bear)
this is easier
attachment.php ?

Got some sensible answers. However, the answers given are : 4 and 16 x root2 :/
13. (Original post by Sidhant Shivram)
attachment.php ?

Got some sensible answers. However, the answers given are : 4 and 16 x root2 :/
Haven't got a pen or pencil (or paper) on me atm but by just looking at the Q-maybe use the change of base rule and try to form a quadratic? (remembering the logarithmic function is defined for positive values of x.
I may be wrong however as I have not tried it out myself.
14. (Original post by Sidhant Shivram)
...

15. (Original post by lazy_fish)

Oops! Got it! thank you so much!

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