Question

Please solve this problem

Answer 1

Rationalise both terms on the LHS and you will get a term in the form of a+broot7

Answer 2

[(√7-1)/(√7+1)]-[(√7+1)/(√7-1)]=[(√7-1)²-(√7+1)²]/[(√7-1)(√7+1)
                                               =[(7+1-2√7)-(7+1+2√7)]/(7-1)
                                               =(7+1-2√7-7-1-2√7)/6
                                               =(-4√7)/6
                                               =(-2√7)/3

a+b√7=0+[(-2√7)/3]
by comparing,
a=0,b=-2/3