Question

Solve x log2 (x + 3) = 4.

Answer 1

Exact Form:

x

=

−

log

(

8

)

−

√

log

2

(

8

)

+

log

(

65536

)

log

(

4

)

,

−

log

(

8

)

+

√

log

2

(

8

)

+

log

(

65536

)

log

(

4

)

Decimal Form:

x

=

2.44179050

…

,

−

5.44179050

…

Answer 2

Answer: x = 13

Work Shown:

`\log_2(\text{x}+3) = 4\\\\\text{x}+3 = 2^4\\\\\text{x}+3 = 16\\\\\text{x} = 16-3\\\\\text{x} = 13\\\\`

The rule I used on the second step was

`\log_b(\text{x}) = y \ \text{ is equivalent to } \ b^y = \text{x}`