Question

How to find the value of x in x^4 = 4 using a scientific calculator?

Answer 1

@phi @Directrix

Answer 2

depends. there are 4 roots.
but in your head
you can take the square root of both sides to get
\[ x^2= \pm 2 \]
and if you take the positive 2, you get \( x= \pm \sqrt{2} \)
which is 2 of the 4 roots.

Answer 3

i actually need to find the decimal form of it.

Answer 4

but how can i use guess and check effectively (w/o it being too time-consuming) to solve for x? @phi

Answer 5

use the rational exponent button from the calculator
\(\Large x^4=4\implies x=\sqrt[4]{4^1}\implies x=4^{\frac{1}{4}}\)

Answer 6

i am asking this question because it is related to (i think) another question. here it is:

there are originally 1000 bacteria in a culture, and 4 hours later there are 4000. find the rate of increase per hour of the bacteria.

Answer 7

exponential growth: y = \(ab^x\)
4000 = 1000\(x^4\)
4000/1000 = (1000\(x^4\))/1000
4 = \(x^4\)

Answer 8

i am just learning algebra 1 and my teacher prefers for me not to use the other sophisticated formula of \(A = Pe^{r(t)}\)

Answer 9

ok

Answer 10

so how can i solve that problem?

Answer 11

@jdoe0001

Answer 12

your calculator can do roots
do
4^(¼)