Question

Hi could someone please help me with this question: I found all the parts, except when the function is defined , should it be y>0 or y>1

Verify linearization: @ pt (pi, 0) = 1+(1/2)y
f_x= sqrt[y+cos^2(x)]
f_y=1/2(y+cos^2x)^(-1/2)
L(x,y)=1+1/2y