2.1.2. \( \frac{(2+d)^{2}}{e^{3}} \) when \( d=2 \) and \( e=-1 \)

Risolvi l'equazione: \( |x| = 7 \) e trova i possibili valori di x.

5. \( |x|=10 \)

2. Make \( \pi \) the subject of the formular \( =\frac{6}{2 \pi} \)

6. \( |7 x|=-63 \)

Write out in full and verify the statements \( S_{1}, S_{2}, S_{3}, S_{4} \), and \( S_{5} \) for the follow \( 18+54+90+\cdots+(36 n-18)=18 n^{2} \) \( 18+54+90+126+162=\square \) (Do not simplify.) Are \( S_{1}, S_{2}, S_{3}, S_{4} \), and \( S_{5} \) true statements? No Yes Which of the following is the next step of the proof? A. Show that \( S_{k+1} \) is true. B. Show that if \( S_{k} \) is true, then \( S_{k+1} \) is true. C. Show that \( S_{n} \) is true. O D. Show that if \( S_{k+1} \) is true, then \( S_{k} \) is true. Write the statement \( S_{k} \) and \( S_{k+1} \).