Math

1. $\int_0^{\frac{3\pi}{4}}\left|\cos x\right|dx\ =\ ?$

2. Two forces 2p and p are acting on a body. If the First force is doubled and second force is increased by 8 unit, then the direction of the resultant remains unchanged. What is the value of p?

3. Assume that the point A (5,6) is a reflection of the point B(-1, 8) in a line,  when a mirror is placed along the line. The equation of the line is -

4. If A and B are two sets, and the complements of A and B are A' and B',  respectively,  then A' - B' is-

5. If a thin light-ray falls upon the X-axis along the line 5x+5y=3 and gets fully reflected, what will be equation of the line of the reflected  ray?