Question

(7y)^2-y(y+1). при y=-1/15решите пж​

Answer 1

(7y)²-y(y+1)

49y²-y²-y

48y²-y

48(-1/15)²-(-1/15)

1)(-1/15)²=-1/15*(-1/15)=1/15*1/15=1/225

2)48*1/225=(48*1)/225=48/225=8/39

3)8/39-(-1/15)=8/39+1/15=40/195+13/195=53/195

Ответ:53/195

Answer 2

To solve the expression (7y)^2 - y(y + 1) when y = -1/15, we need to substitute the value of y into the expression and then perform the calculations. Let's do that step-by-step:

Step 1: Substitute y = -1/15 into the expression: (7 * (-1/15))^2 - (-1/15) * ((-1/15) + 1)

Step 2: Simplify the expression: ((-7/15)^2) - (-1/15) * (-14/15)

Step 3: Square the fraction and simplify: (49/225) - (-14/15) * (-1/15)

Step 4: Multiply the fractions and simplify further: (49/225) - (14/225)

Step 5: Combine the fractions: (49 - 14) / 225

Step 6: Final calculation: 35 / 225

Step 7: Simplify the fraction if possible: 7 / 45

So, the value of the expression (7y)^2 - y(y + 1) when y = -1/15 is 7/45.