Question
Which one of the following is also known as Long run
average cost curve?Solution
The Long Run Average Cost (LRAC) Curve is also called the: Envelope Curve because: • It is formed by enveloping (touching) the minimum points of all possible Short Run Average Cost (SRAC) curves. • Each point on the LRAC corresponds to the lowest possible cost for producing a given output when all inputs are variable. Other options: • Basket Curve — No such concept in economics. • Wallet Curve — Not an economics term. • Production Possibility Curve — Shows maximum production combinations of two goods.
If sec A + tan A = 3 and sec A - tan A = (1/3), find the value of cos A.
In a right triangle ABC, angle B = 90°. If tan A = 3/4 and the length of the hypotenuse is 25 cm, find the area of the triangle.

- Find the value of sin²10° + sin²80° + cos²15° + cos²75°.
If A lies in the first quadrant and 6 tan A = 5, then the value of 8 sin A−4 cos A / cos A+2 sin A is :
Find the value of tan(75°) using the identity for tan(A+B).

If tanθ = x then find the value of cos 2θ?
Simplify:
8sin 27° sec 63° + 3cot 64° cot 26°