question_answer 1)

When \[a=0,b=-1,\] find the value of the given expressions: (i) \[2a+2b\]                       (ii) \[2{{a}^{2}}+{{b}^{2}}+1\]                     (iii) \[2{{a}^{2}}b+2a{{b}^{2}}+ab\]          (iv) \[{{a}^{2}}+ab+2\]

Answer:

                (i) \[2a+2b=2(0)+2(-1)=0-2=-2\].                 (ii) \[2{{a}^{2}}+{{b}^{2}}+1=2{{(0)}^{2}}+{{(-1)}^{2}}+1\] \[=0+1+1=2.\]                 (iii) \[2{{a}^{2}}b+2a{{b}^{2}}+ab=2{{(0)}^{2}}(-1)+2(0){{(-1)}^{2}}\]\[+(0)(-1)\] \[=0+2+0=2.\]                 (iv) \[{{a}^{2}}+ab+2={{(0)}^{2}}+(0)(-1)+2\] \[=0+0+2=2\].