Answer:
-1/2
or -2/4
Step-by-step explanation:
they are the same
<span>The square root of -16 is an imaginary number and a complex number. Sqrt(-16)=4i. We use the i to indicate that the number is imaginary since there is no number that can be multiplied by itself to get a negative number (a negative times a negative is a positive, and a positive times a positive is also a positive). So the use of i tells you immediately that it's an imaginary number. You can tell the number is complex because it has both a real and an imaginary part and could be written in the form a+bi, where a is a real number and bi is an imaginary number. In this specific case, the real part (a) is 0 and the imaginary part (bi) is 4i.</span>
Zero because is itself an eq.
P(t) = 40(2)^(kt)
<span>when t=10, (1990), N = 55 </span>
<span>55 = 40(2)^(10k) </span>
<span>1.25 = 2^(10k) </span>
<span>take the ln of both sides, hope you remember your log rules </span>
<span>10k = ln 1.25/ln 2 </span>
<span>10k = .32193 </span>
<span>k = .032193 </span>
<span>so P(t) = 40(2)^(.032193t) </span>
<span>in 2000, t = 20 </span>
<span>P(20) = 40(2)^(.032193(20)) </span>
<span>= 62.5 million </span>
<span>for the formula </span>
<span>P(t) = a(2)^(t/d), d = the doubling time </span>
<span>so changing .032193t to t/d </span>
<span>= .032193t </span>
<span>= t/31.06 </span>
<span>so the doubling time is 31.06 </span>
<span>another way would be to set </span>
<span>80 = 40(2)^(.032193t) </span>
<span>2 = (2)^(.032193t) </span>
<span>.032193t = ln 2/ln 2 = 1 </span>
<span>t = 31.06</span>
Isn't that a multiple chose