Question

(3a-2)(3a+2)-3a(a-3) при a=0.2 ​

Answer 1

(3*0.2-2) (3*0.2+2) -3*0.2(0.2-3)=

=-1.4*2.6 - 0.6(-2.8)=

= -3.64 -(-1.68)= -1.96

Answer 2

To evaluate the expression (3a-2)(3a+2)-3a(a-3) when a = 0.2, we substitute the value of a into the expression and perform the calculations.

Let's substitute a = 0.2:

(3(0.2)-2)(3(0.2)+2)-3(0.2)(0.2-3)

Simplifying each part:

(0.6-2)(0.6+2)-3(0.2)(-2.8)

(-1.4)(2.6)-3(0.2)(-2.8)

Now, we perform the multiplications:

-3.64-3(0.2)(-2.8)

-3.64-0.168(-2.8)

-3.64+0.4704

The result is:

-3.1696