f(x)=∣∣
∣
∣∣cos(x+x2)sin(x+x2)−cos(x+x2)sin(x−x2)cos(x−x2)sin(x−x2)sin(2x)0sin(2x2)∣∣
∣
∣∣differentiatingw.r.txwegetf′(x)=(1+2x)∣∣
∣
∣∣−sin(x+x2)cos(x+x2)sin(x+x2)sin(x−x2)cos(x−x2)sin(x−x2)sin(2x)0sin(2x2)∣∣
∣
∣∣+(1−2x)∣∣
∣
∣∣cos(x+x2)sin(x+x2)−cos(x+x2)cos(x−x2)−sin(x−x2)cos(x−x2)sin(2x)0sin(2x2)∣∣
∣
∣∣+2∣∣
∣
∣∣cos(x+x2)sin(x+x2)−cos(x+x2)sin(x−x2)cos(x−x2)sin(x−x2)cos(2x)02xcos(2x2)∣∣
∣
∣∣⇒f′(0)=∣∣
∣∣010010000∣∣
∣∣+∣∣
∣∣10−1101000∣∣
∣∣+2∣∣
∣∣10−1010100∣∣
∣∣=0+0+2(1)=2