Question

3. Find the sum of following, if a = 1, b = 2 and c=3:

(a) 7a-5b+3c; 2a - b+c; 3a+2b.
(b) 2a²+3b²+3c² ; -a² - b² - c² ; -a² - b² +c²
(c) a² +b² +c²; – a² – b²; b² – c²
(d) ab + bc + ca; ab-bc-ca; - ab + bc + ca
(e) a² + ab +b² ; b² + bc +c² ;c² + ac + a² ​

Answer 1

Answer:

a) 7(1)-5(2)+3(3)=7-10+9=9+7-10=16-10=6.(b) 2(1)^2+3(2)^2+3(3)^2=2+12+27=41.(c) -a^2-b^2= -1^2-2^2=1+4=5.(d) put values of a,b,c.(e) a^2+ab+b^2= (1)^2+1*2+(2)^2=1+2+4=7. Make sure that the left questions should be done by you as simple Home-Work.