A) y=ae3x+be5x⇒y1=3ae3x+5be5x⇒y1=3y+2be5x⇒y2=3y1+5(y1−3y)⇒y2−8y1+15y=0
B) xy=aex+be−x+x2⇒xy1+y=aex−be−x+2x⇒xy2+2y1=aex+be−x+2⇒xy2+2y1=xy−x2+2⇒xy2+2y1−xy+x2−2=0
C) ax2+by2=1⇒2ax+2byy1=0⇒ax+byy1=0 ...(1)
⇒a+b(y1)2+byy2=0⇒a+b[(y1)2+yy2]=0 ...(2)
Multiplying (2) by x and subtracting from (1), we get
bx[yy2+y12]−byy1=0⇒x{yy2+(y1)2}=yy1
D) y=asin(4x+b)⇒y1=4acos(4x+b)⇒y2=−16sin(4x+b)⇒y2=−16y