If 8√x2=16, what is the value of x?
16x449y2+49y416x2+2xy=(4x27y+7y24x)2
If S=4−9x+16x2−25x3+36x4−49x5+......∞. Find the value of S for x=−12.
If S=4−9x+16x2−25x3+36x4−49x5+......∞. Find the value of S for x=−12. ___