solve the folowing equations for x round nonexact answers to
solve the folowing equations for x. round non-exact answers to three decimal places.
5(1.031)^x =8
3 x 2^x + 8 = 25
e^x+4 =10
10 e^3x - e = 2e^3x
3log (2x+6) =6
2ln (3x) +5 =9
Solution
5(1.031)^x = 8
dividing both sides by 5
(1.031)^x = 8/5
taking ln on both sides
x * ln (1.031) = ln (8/5)
x = ln (8/5) / ln (1.031) = 15.40
2) 3x 2^x + 8 = 25
subtracting 8 from both sides
3x 2^x = 25 - 8 = 17
dividing both sides by 3
2^x = 17/3
taking ln on both sides
x ln 2 = ln ( 17/3)
x = ln (17/3) / ln 2 = 2.50
3) e^x + 4 = 10
subtracting 4 on both sides
e^x = 6
x ln e = ln 6
x = ln 6 = 1.79
