First we need to multiply to make the fractions have equal denominators so we can add/subtract.
math: 1/3 x 4/4=4/12
science: 1/4 x 3/3=3/12
Now we can find the time she spent on history (I assume this is what you are looking for)
Total time-math time<span>-science time=history time</span>
12/12-4/12-3/12
=5/12
Amy spent 5/12 of her time working on history.
Answers:
(sin40)/(cos40) and
(cos50)/(sin50)
Answer: She is incorrect because 0 + 0 = <u>0</u>
Answer:
x=2+ or - the square root of 3
Step-by-step explanation:
solve the equation for x by finding a, b, and c of the quadratic then applying the quadratic formula.
All three series converge, so the answer is D.
The common ratios for each sequence are (I) -1/9, (II) -1/10, and (III) -1/3.
Consider a geometric sequence with the first term <em>a</em> and common ratio |<em>r</em>| < 1. Then the <em>n</em>-th partial sum (the sum of the first <em>n</em> terms) of the sequence is

Multiply both sides by <em>r</em> :

Subtract the latter sum from the first, which eliminates all but the first and last terms:

Solve for
:

Then as gets arbitrarily large, the term
will converge to 0, leaving us with

So the given series converge to
(I) -243/(1 + 1/9) = -2187/10
(II) -1.1/(1 + 1/10) = -1
(III) 27/(1 + 1/3) = 18