Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:
Using each condition individually a+b cannot be found out.
Using both of them together, we get ax^4+bx^3=a^2+b^2=5
Hence we can have possible values of a,b as (-1,-2), (1,2), (-1,2), (1,-2)
Then posssible values of a+b are -3,3,1,-1
Both conditions together are also Insuff
Hence answer should be E