(5c-11d)*(5c+11d)-25c2=25c2-121d2-25c2=-121d2
не за что
1)-sina*sina/tga*sina=-sina:sina/cosa=-sina*cosa/sina=-cosa
2)cosa+cosa-tga+tga=2cosa
1.
a0<span> = 1 (</span>a<span> ≠ 0)</span>
2.
a1<span> = </span>a
3.
<span>an</span><span> · </span><span>am</span><span> = </span>a<span>n + m</span>
4. (
<span>an</span>)m<span> = </span><span>anm</span>
5.
<span>an</span><span>bn</span><span> = (</span>ab)n
<span><span><span>6. <span>a-n</span> = </span>1</span><span>an</span></span>
<span><span>7. <span>an</span><span> = <span>an - m</span></span></span><span>am</span></span>
8.
a<span>1/n</span><span> = </span>n√<span>a</span>
Ctg²t·(cos²t-1)+1=ctg²t·(-(1-cos²t))+1=ctg²t·(-sin²t)+1=(cos²t/sin²t)·(-sin²t)+1=
=-cos²t+1=sin²t