What is the simplified value of (cos4 A ? sin4 A) ?

Correct Answer: 1

Correct Answer: 1

Correct Answer: 4/3

Correct Answer: 154/27

Correct Answer: 666

Correct Answer: Each fraction is equal to 1/2 or -1

Explanation:

a/(b+c) = b/(c+a) = c/(a+b)

Taking reciprocal and adding 1 to each ratio we get;

(b+c)/a + 1 = b/(c+a) + 1 = c/(a+b) + 1

Or (a+b+c)/a = (a+b+c)/b = (a+b+c)/c

So this can only be equal when a=b=c or a+b+c = 0

When a=b=c we get

a/(b+c)= ½When a+b+c = 0 we get

b+c = -a

So a/(b+c) = -1

So the ratios are ½ or -1

Correct Answer: xy/x+Y

Explanation:

Correct Answer: a/b = c/d

Explanation:

(4a+7b)(4c-7d) = (4a-7b)(4c+7d)

(4a+7b)/(4a-7b) = (4c+7d)/(4c-7d)

Using componendo and dividendo

(4a+7b)+(4a-7b) / (4a+7b)-(4a-7b)

= (4c+7d)+(4c-7d) / (4c+7d)-(4c-7d)

Or 8a/14b = 8c/14d

Or a/b = c/d

Correct Answer: 4

Explanation:

Let 2+?2+?2..... = t
2+?t = t
t - 2 = ?t
t = 4

Correct Answer: 6/?+4

Explanation: