Question

2^2x -6.2^x +8 =0

Answer 1

say k = \(\large 2^x\)

Answer 2

\(\large 2^{2x} -6.2^x +8 =0\)

\(\large (2^{x})^2 -6.2^x +8 =0\)

Answer 3

plugin k and you will see a quadratic in k
solve k

Answer 4

ok but how abaout the number 8???

Answer 5

wat do u get after putting \(2^x=k\)
?

Answer 6

we get this :-

\(\large k^2-6k+8=0\)

Answer 7

this is just a quadratic equation
you knw how to solve a quadratic equaiton ha ?

Answer 8

yes

Answer 9

good, factor it and solve k first

Answer 10

humm ok ok i got it k thanks

Answer 11

sure ?

Answer 12

\(\large (k-2)(k-4) = 0\)

\(k = 2, k=4\)

Answer 13

i get the answer are -2 and -4

Answer 14

yes..

Answer 15

when k = 2,
\(2^x = k\)
\(2^x = 2^1\)

\(x = 1\)

Answer 16

when k = 4,
\(2^x = k\)
\(2^x = 4\)
\(2^x = 2^2\)

\(x = 2\)

Answer 17

so the solutions are : 1, 2

Answer 18

yup yup

Answer 19

cool :)