Answer:
1) 45
2) 6x^2-4xy+10y^2
Explanation:
1) Given f(a, b) = 3a^2 – 2ab + 5b^2 , determine (a) f(-2, 3)
Replace a with (-2) and b with (3):
3(-2)^2-2(-2)(3)+5(3)^2
3(4)-2(-6)+5(9) *Took care of exponents and performed some multiplication in the middle term.
12-12+45 *performed more multiplication
0+45 *additive inverses property applied
45 *performed some addition
2) Given f(a, b) = 3a^2 – 2ab + 5b^2 , determine f(x+y, x-y)
Replace a with (x+y) and b with (x-x-y):
3(x+y)^2-2(x+y)(x-y)+5(x-y)^2
*Explained binomial squares
3(x^2+2xy+y^2)-2(x+y)(x-y)+5(x^2-2xy+y^2)
*Expand product of the sum of two numbers with the difference of said numbers
3(x^2+2xy+y^2)-2(x^2-y^2)+5(x^2-2xy+y^2)
*Distribute
3x^2+6xy+3y^2-2x^2+2y^2+5x^2-10xy+5y^2)
*Combine like terms
6x^2-4xy+10y^2