NDA2022MathematicsDifferentiationActual
If x^y y^x=1 , then what is d y d x at (1,1) equal to?
Options
- A-1
- B0
- C1
- D4
Correct answer
A. -1
Step-by-step solution
x ^ y y ^ x =1 Taking log both sides aligned & y x+x y=0 & y^ x+ y x + y+ x y y^ =0 aligned put x =1, y =1 aligned & y ^ (1)+1+ (1)+ y ^ =0 & 0+1+0+ y ^ =0 y ^1=-1 aligned