5X²-[X²(5X²-2X)-(2X²-3X)]
= 5X²-(5X^4-2X^3-2X²+3X)
= 7X²-5X^4+2X^3-3X
= 7 * 1/4 - 5 *1/16 - 2*1/8 + 3*1/2
=43/16