how do you solve to find the value of x, when it's an exponent? What would "x" be if, 4^x=1783 ? and while I'm on it...what is the derivative of f(x)= 15sin(x)-4(tan) ?
2007-01-27 13:53:54 · 5 answers · asked by nyadastar 2 in Science & Mathematics ➔ Mathematics
4^x=1783
log 4^x = log 1783
xlog4 = log 1783 [Law of logarithms]
x= log 1783/log4
x= 5.4
dy/dx= 15cosx -4sec^2x
2007-01-27 14:02:38 · answer #1 · answered by ironduke8159 7 · 0⤊ 0⤋
Well I can tell you how to find the value of x.. You must use logs. Take the log of both sides, you get: log(4^x)=log(1783). Using-I think it is- the Logarithm of a Power property, this equals: x(log4)=log(1783). From there all you have to do is log(1783)/(log4). Just divide those, and you get the answer. I hope that was helpful!
2007-01-27 22:04:02 · answer #2 · answered by coolcat607 2 · 0⤊ 0⤋
To answer the first queston you would apply the log function to both sides: log(4^x)=x*log(4)=log(1783)....x=log(1783)/log(4).
To answer your second question, f`(x)=15cos(x)+4sec^2(x)
2007-01-27 22:03:05 · answer #3 · answered by bruinfan 7 · 0⤊ 0⤋
4^x=1783
log 4^x= log 1783
x log4= log1783
x= log1783/log4
2007-01-27 21:59:32 · answer #4 · answered by 7 · 0⤊ 0⤋
ironduke8 is right
x after (tan) is missing in your question
2007-01-27 22:05:09 · answer #5 · answered by grandpa 4 · 0⤊ 0⤋