00:02
To question, given that 7x square plus 3xy minus 5 is equal to 7.
00:10
So consider 7x square plus 3xy minus y square is equal to 7, differentiate with respect to x, so dx by dx, 7x2 plus 3xy minus 5 square is equal to t by d x 7 so 7 d by d by d x square plus 3 d by d x x into y minus 1 by d x y x x into y x 0 to 0 so that is equal to 7 into 2 x plus 3 into 1 into y plus x t by x t by d x so minus 2y, d .y, d .yx is equal to 0.
01:12
So that is equal to 7 into 2x plus 3y, plus x, t by dx minus 2y, t by dx, is equal to 0.
01:32
So that is equal to 14x plus 3y, y, plus 3x, dye by, dx, minus 2y, dx, minus 2y, dyx, minus 2y ,000...